## 1. Biographical Sketch



Stumpf's intellectual biography is rich and complex due to his
long university career that lasted for more than 50 years, his
academic achievements, and his philosophical work. To complete this
biographical sketch, the reader is invited to consult Stumpf's
autobiography (published in 1924) and Sprung's biography,
published in German under the title *Carl Stumpf - Eine
Biografie* (2006).


* 1848 Carl Friedrich Stumpf was born on April 21, 1848 in
*Wiesentheid* in Franconia, Germany.
* 1859-1863 Attended the Gymnasium in Bamberg, studied music
and composed several pieces.
* 1864-1865 Attended the Gymnasium in Aschaffenburg where he
studied Plato with Hocheder.
* 1865 Entered the University of Wurzburg and during his first
year studied aesthetics and law
* 1866 Met Franz Brentano on July 14, 1866 during the
*disputatio* of his habilitation and then decided to study
philosophy with Brentano. From 1867 to 1870 he attended
Brentano's lectures on the history of philosophy, metaphysics,
Comte and positivism and logic.
* 1867-1868 Because Brentano had not been habilitated to
supervise dissertations, it was recommended that Stumpf study with
Hermann Lotze in Gottingen. He attended Lotze's lectures on
psychology, history of philosophy since Kant, philosophy of nature,
and practical philosophy. He also attended lectures from the
physiologist G. Meissner and the physician W. Weber.
* 1868 Graduated on August 13, 1868 with a dissertation on Plato and
then returned to Wurzburg to study with Brentano.
* 1869-1870 Entered the ecclesiastical seminary in
Wurzburg and resigned in July 1870 due to the influence of
Brentano and Lotze.
* 1870 Returned to Gottingen to prepare his habilitation on
mathematical axioms under the supervision of Lotze and successfully
defended it in October 1870.
* 1870-1873 Lectured at the University of Gottingen where
he founded the Eskimo society along with his friend Felix Klein. He
also met G. Fechner and probably G. Frege, who studied in
Gottingen during this period.
* 1873 Published an important treatise on the origin of space
perception, and dedicated it to Lotze.
* 1873-1879 Was appointed to his first professorship at the
University of Wurzburg at the age of 25 to replace Brentano, who
moved to Vienna in 1874.
* 1878 Married Hermine Biedermann (1849-1930).
* 1879-1884 Moved to Prague and was joined there by his friend
Anton Marty in 1880. He developed professional contacts with Mach and
maintained a close relationship with Ewald Hering.
* 1882 Was visited by William James in Prague and this encounter led
to the beginning of a lasting friendship between both
philosophers.
* 1883 Published the first volume of *Tonpsychologie*.
* 1884-1889 Replaced H. Ulrici at the University of Halle and
became a colleague of Georg Cantor and J. E. Erdmann.
* 1887 Husserl submitted his habilitation thesis on the origin of
the concept of number under Stumpf's supervision.
* 1889-1894 Arrived in Munich in 1889 as the successor to K.
Prantl.
* 1890 Published the second volume of *Tonpsychologie.* He
also worked with H. Ebbinghaus, H. von Helmholtz, and G. E.
Muller, among others, on the prestigious journal *Zeitschrift
fur Psychologie und Physiologie der Sinnesorgane*, of which
Stumpf was one of the founding editors.
* 1891 Involved in a controversy with W. Wundt and his students on
the use of experiments and on Fechner's law.
* 1894 Joined the philosophy faculty in Berlin after a long period
of hesitation; marked the beginning of a new period in his
intellectual life.
* 1896 Presided along with T. Lipps the third International Congress
of Psychology in Munich.
* 1898 Joined the Academy of sciences in Berlin. Founded the journal
*Beitrage zur Akustik und Musikwissenschaft*, which
contains many treatises written by Stumpf and his students.
* 1900 Founded the Institute of Psychology in Berlin, which gave
rise to Gestalt Psychology; started the Phonogramm-Archiv in Berlin on
the basis of some phonographic recordings of a Siamese company
performing in Berlin; in the same year along with F. Kemsies he
started the Berlin *Gesellschaft fur
Kinderpsychologie*.
* 1900-1901 Husserl's groundwork *Logical
Investigations* was published and dedicated to Stumpf.
* 1904 Asked by the Board of Education to investigate the well-known
case of "clever Hans" and in 1907 the results of this
investigation were published by Stumpf and his assistant O. Pfungst in
the book *Clever Hans (The Horse of Mr. von Osten): A Contribution
to Experimental Animal and Human Psychology*.
* 1906-1907 Published three important treatises, which were
extensively discussed by philosophers and psychologists:
"Erscheinungen und psychische Funktionen," "Zur
Einteilung der Wissenschaften" and "Uber
Gefuhlsempfindungen."
* 1907-1909 Accepted the honorific position of rector of the
University of Berlin; pronounced his first address "Renaissance
of Philosophy" on the state of philosophy in Germany since
Lotze.
* 1908 Robert Musil, the author of *The Man without
Qualities*, wrote a dissertation on Mach under the supervision of
Stumpf.
* 1909 Wolfgang Kohler received his PhD with a dissertation
under the supervision of Stumpf, which was published under the title
"Akustische Untersuchungen I." Trip to Cambridge to
celebrate the 100th anniversary of Charles Darwin.
* 1911 Published *Die Anfange der Musik* in which he
summarized the results of his research on ethnomusicology.
* 1912-1913 Established a station for anthropoids in Tenerife
by the Academy of Sciences; as a member of the Academy, Stumpf
recommended his student W. Kohler as director of this station.
Kohler began his investigations in 1913 and published the results
in his classic book *The Mentality of Apes* (1917).
* 1921 Was appointed professor emeritus in Berlin and continued to
teach philosophy in Berlin until the summer 1923.
* 1922 W. Kohler succeeded Stumpf as director of the Institute
of Psychology in Berlin.
* 1923 With his assistant E. M. von Horbostel, Stumpf edited four
volumes of the classical *Sammelbande fur vergleichende
Musikwissenschaft.* The fourth volume contains a study on popular
music in Romania by the well-known composer Bela
Bartok.
* 1923 *Festschrift* in honor of Stumpf's 75th
anniversary in the Gestaltist journal *Psychologische
Forschung*; this volume includes contributions by his students A.
Gelb, C. von Allesch, W. Kohler, K. Koffka, M. Wertheimer, and K.
Lewin, among others.
* 1926 Published the results of extensive research on the nature of
vowels and the sounds of speech in *Die Sprachlaute;
experimentell-phonetische Untersuchungen*.
* 1927/1928 Published a short biography on his friend W. James,
based on their correspondence: *William James nach seinen
Briefen*.
* 1928 Published *Gefuhl und Gefuhlsempfindung*, an
important collection of papers on emotions and feelings.
* 1928 Celebrated his 80th anniversary for which an
allocution was given by his friend and colleague Max Planck.
* 1936 Carl Stumpf died on December 25 in Berlin at the age of
88.
* 1939-1940 With the recommendation of Max Planck, his son
Felix Stumpf published the two volumes of his monumental work
*Erkenntnislehre*.


## 2. Historical Background



The two most important names associated with the young Stumpf's
philosophical formation are those of Franz Brentano and Hermann Lotze.
His debt to Brentano is well documented in his autobiography and in
the three biographies, which Stumpf (1918, 1919, 1922) devoted to him
after his death in 1917. But opinions diverged regarding
Stumpf's later position to Brentano's philosophical
program. Some claim that Stumpf is a truly orthodox Brentanian (K.
Schuhmann, 1996) while others argue that Stumpf gradually distanced
himself from Brentano's thinking and moved closer to that of
Lotze (Ewen, 2008 Milkov 2015). The truth must lie somewhere in the
middle if we are to judge the matter in light of Stumpf's many
testimonies in his biographical articles and in his substantial
correspondence with Brentano where he unequivocally acknowledges his
debt to Brentano.



Stumpf's debt to Lotze's philosophy is certainly
significant but it is not very well documented. Most studies on the
relationship between Stumpf and Lotze emphasize Lotze's theory
of local signs (see W. R. Woodward, 1978; Fisette, 2006, 2012; B.
Centi, 2011) and the problem of the origins of space perception, which
is in fact the central theme of Stumpf's *Raumbuch*
(Stumpf, 1873; M. Kaiser-El-Safti, 1994; D. Pradelle, 2015). In this
book, dedicated to Lotze, Stumpf offers a summary of the debates
between philosophers, scientists, and psychologists on the origins of
space perception since Fechner. In the preface to this book, Stumpf
explains that his starting point is the controversy between nativism
and empiricism triggered by Helmholtz in his *Handbuch* (H. von
Helmholtz, 1910, vol. 3, SS 25) while his inspiration lies in
Lotze (1852) *Medizinischer* *Psychologie*.
Lotze's influence on the young Stumpf's thought is not
limited to his doctrine of local signs as Stumpf repeatedly emphasized
(R. Rollinger, 2008; N. Milkov, 2015; D. Fisette, 2009b). Beyond the
question of influence, Stumpf assigns a central role to Lotze's
thought in the history of philosophy and associates him with a
renaissance of philosophy in the mid-nineteenth century (Stumpf,
1907).



From his two mentors Brentano and Lotze, Stumpf inherited a marked
interest in the history of philosophy. This interest was not strictly
historiographical**:** his point of departure was
Brentano's theory of the four phases in the history of
philosophy, and he worked out his own philosophy of history, which
constitutes the basis of his diagnosis on the state of philosophy in
the nineteenth century, which is inseparable from the way he conceived
of philosophy. In his first address as the rector of the university of
Berlin delivered in 1907 under the title "Renaissance of
Philosophy," exactly a hundred years after Fichte's
"Address to the German Nation" at the same university,
Stumpf applied this philosophy of history to the nineteenth century
and asked whether philosophy at this time belonged to an ascending
stage of history and whether it tended towards a renaissance of
philosophy. He identified two factors which marked the development of
philosophy during this period: the empty space left by the decline of
speculative philosophy of German idealism during the first half of the
nineteenth century, and the remarkable development of psychology and
of the physiology of senses during the second half of this century,
due to the works of physiologists and physicists such as Fechner,
Weber, Hering, and Helmholtz. These two factors corresponded to two
divergent philosophical orientations at the time when Stumpf was
undertaking his studies in philosophy. The first was the Kantian
tradition in its different ramifications, including Neo-Kantianism;
the second corresponds to what he called
*Erfahrungsphilosophie* or philosophy of experience, which
began with Fechner and above all with Lotze's works on
psychology and more particularly on the problem of space perception.
Although it does not represent a homogeneous tradition, the philosophy
of experience refers to common features of several schools and
currents of thought which attempted to bring philosophy closer to
natural sciences, and more particularly to the "new
psychology", which was neglected and relegated to the background
by the other tradition. Corresponding to these two orientations are
two different ways of doing philosophy: the philosophy of experience
starts from below, and like any empirical science, uses the inductive
method. They differ from an *a priori* and speculative approach
to philosophy which favors an autocratic regime entirely disconnected
from the empirical.



As B. Russell pointed out in his *Essay on the Foundations of
Geometry*, Stumpf's main criticism against Kant and *a
priori* philosophy concerns the dichotomy between form and matter,
more precisely the postulate of *a priori* forms of thought and
sensibility. This criticism was already clearly formulated in his
*Raumbuch*, where he examined the nativism-empiricism
controversy on space perception, prepared some years earlier by
Helmholtz in the third book of his *Handbuch*. This controversy
is at the origin of an important division in the middle of the
nineteenth century within the new psychology proponents, between
empiricism advocated mainly by Helmholtz and Wundt; and nativism
which, according to Helmholtz, characterizes the works of Ewald Hering
in physiology, the latter of which in fact exercised an influence on
the Brentano school and to a certain extent on Gestalt psychology.
Instead of using Helmholtz's terminology, as did most
historians, Stumpf preferred the term phenomenology to designate the
study of phenomenal experience, which occupied center stage in the
field of physiology and psychology. In his *Raumbuch* Stumpf
takes a stand in favor of a moderate form of nativism, according to
which space is a unitary sense, its content is perceptible in an
immediate and direct way, and it is inseparable from sensory qualities
such as color and sound. Consequently, space and color constitute one
and the same content, of which they are partial contents or
attributes. They are in a relation of logical dependence with the
phenomena of which they form a part. Hence, extension and color form a
concrete whole which can only be separated through abstraction. From
this point of view, the concept of space, as any concept, draws upon
its origin in sense perception and is, to use the Scholastic
expression, an *abstracta cum fundamento in re*.


## 3. Philosophy of Mind



Philosophy of mind or what is called descriptive psychology represents
one of the main axes of Stumpf's program in philosophy. His
treatises in this domain are quite diversified, ranging from animal
and developmental psychology to acoustic psychology and Gestalt
psychology. Other than his *Raumbuch*, the book that made
Stumpf renowned in psychology is *Psychology of Sound*
(published in two volumes in 1883 and 1890) which was widely received
in Germany and England (see reviews by P. Natorp, A. Meinong, T. Lipps
and J. Sully). In this book, as in most of his treatises on
psychology, Stumpf's approach is similar to that of
Brentano's descriptive psychology. It differs from experimental
and physiological psychology in that it conceptually analyses and
describes what physiological psychology explains through the
descriptive apparatus of the natural sciences such as biology or
physiology. Between these two branches of psychology there is a form
of division of labor wherein the first analyses and describes what the
other explains. However, descriptive psychology has a methodological
priority over experimental psychology in that the analysis and
description of the *explanandum* is a prerequisite to its
explanation. The two main tasks assigned to descriptive psychology are
the analysis and the classification of mental states (also called acts
or mental functions). In his influential study entitled
"Phenomena and Mental Functions," Stumpf shows how
phenomena are closely linked in that they form a real unity, which can
only be separated by abstraction. He conceives of phenomena as unitary
wholes and not as aggregates, and claims that they are perceived as
concrete and unitary wholes. As such, phenomena are the contents of
sensations that are characterized by certain properties or attributes,
for example extension, intensity, brightness, etc., and these contents
of sensations are first-order phenomena as opposed to second-order
phenomena like "mnemonic images" and phenomena such as
color or sound, to the extent that they "are merely
represented." Although Stumpf rarely uses the concept of
intentionality, one might say that mental functions are distinct from
physical phenomena in that they are related to their objects by
intentional relations.



Psychical functions have a specific structure that is characterized by
the distinction between the content of a function and its relation to
an object. This relationship is characterized by the notion of
specific content, to which Stumpf refers with the concept of
*Gebilde* (product), and by the quality and matter of an act.
In an act of judgment, for example, the quality of an act consists in
an affirmation or a negation, and it is characterized linguistically
by the copula "is" or its negation. The
"matter" (*Materie*) of a judgment is what remains
when one disregards the affirmation and negation, i.e. the mere
complex of presentations (subject and predicate without the copula).
In addition to its quality and matter, the judgment conveys a specific
"formation" or product (*Gebilde*) that Stumpf
sometimes calls a state of affairs. They are "correlates"
of thought and distinguish themselves from the individual act, of
which they are the content, through their objective character. All
other functions, from the simplest to the most complex, have their
specific content. For example, the act of abstraction, which is
responsible for the formation of concepts, has a concept as its
specific content. In the field of more complex functions such as
emotion, desire, and will, Stumpf maintains that we must also
presuppose specific contents which he calls values.



Descriptive psychology's second task is the classification of
acts or psychical functions. This classification is based on the
distinction between two classes of acts: intellectual and emotional
functions. All functions that fall under either of these two classes
have relationships ranging from the simplest to the most complex, so
that functions of the second class presuppose, and are based on, lower
level functions of the first class. This class of intellectual
functions subsumes all acts ranging from sense perception to judgment.
Sense perception in this classification has a particular status
because it gives direct access to first-order phenomena and as such it
is the function of consciousness (attention) through which something
is noticed or apprehended. It serves as the foundation of all
functions in that it provides them with their sensory material.
Between perception and judgment, there is a series of intermediate
acts: the act of presentation, which has as content second order
phenomena, the act of abstraction and what Stumpf calls the acts of
synthesis, whose specific contents are sets (*Inbegriffe*).



From the class of intellectual functions, Stumpf sets apart the class
of feelings or emotional functions. Stumpf's works in the field
of emotions led to a debate with Brentano and were the subject of many
discussions, particularly by the American psychologist E. B.
Titchener. (E. B. Titchener, 1908, 1927; R. Reisenzein and W.
Schonpflug, 1992; D. Fisette, 2013) At issue was whether the
nature of pleasure provided by an object such as a work of art, for
instance, is intentional, as was the case in Brentano's theory
wherein it is closely related to the class of emotions, or phenomenal
as in Husserl and the sensualist theories of James and Mach. Stumpf
claims that there is a specific difference between sense-feelings
(bodily pleasure, pain, etc.) which are sensory qualities like sound
and color, and emotions (joy, sadness, anger, disgust, etc.) which are
intentional states directed towards states of affairs. Between
emotional and intellectual functions, there is the same relation of
foundation as that between judgment and perception, since judgment, or
more precisely states of affairs, are presupposed by emotional
functions which, although more complex, are nevertheless structured in
the same way. In addition to emotions, this class of feelings subsumes
the acts of desire and will, upon which the field of ethics is based.
Between emotions and the will, there is a hierarchy comparable to that
of the class of intellectual states, with the difference being however
that the phenomenal basis of the class of emotional acts is nothing
other than sense-feelings (pleasure and displeasure). Emotions belong
to the subclass of passive feelings while desire and will belong to
the subclass of active feelings. Feelings are passive in that they
have something existent as an object (that is any object of a true
judgment) while active feelings are related to a duty (object of a
voluntary act). Values are the specific content of the class of active
feelings (desire and will) while the contents of an emotion are
values. Emotions are evaluative states concerning the content of a
judgment and the evaluative element of emotions lies in the positive
or negative stand taken with respect to the judged state of affairs.
The difference between these two classes of acts lies therefore in
their quality, meaning their negative or positive stand
(*Stellungsnahme*) regarding their object: affirmation and
negation in the case of judgment, love and hate in the case of the
entire class of feelings. The relation of foundation between emotions
and judgments or beliefs presupposes, on the one hand, a causal
relation between states of belief and valuation (or stand), and on the
other hand, an intentional relation between the content of belief and
the emotion. From this point of view, jealousy, to use Stumpf's
example, would be a negative stand and a valuation of the state of
affairs that a given person possesses and which another person wants
or covets for herself, but which she does not possess; and this state
is caused by the belief or judgment (true) that this state of affairs
exists (*besteht*).


## 4. The Classification of Sciences



The starting point of Stumpf's classification is the cardinal
distinction made in Brentano's *Psychology* *from an
Empirical Standpoint* between two classes of phenomena, physical
phenomena and mental phenomena, or what Stumpf calls sensory phenomena
and psychical functions. (R. Rollinger, 2008b) The domain of psychical
functions, to which internal perception gives access, belongs to
descriptive psychology which constitutes the foundation of one of the
two branches of Stumpf's classification of sciences, namely the
human sciences (*Geisteswissenschaften*). Human sciences such
as aesthetics and ethics, are closely related to the major classes of
the simple functions such as the class of emotions in ethics, for
instance, and are defined as the sciences of complex functions.
(Stumpf, 1906a, p. 21) The other branch is that of the natural
sciences and it is based on physics. In the perspective of
Stumpf's *Erfahrungsphilosophie*, physics takes as its
starting point the phenomena of external perception, and its task is
to explain the regularity of phenomena by using the laws of physics.
But Stumpf is not a phenomenalist as he advocates instead a form of
critical realism that he conceives as the antithesis of phenomenalism
such as that which he attributes to classical empiricism and to E.
Mach. Nevertheless, Stumpf agrees with the latter that all concepts,
including the concept of causality, originate from the contents of
sensory experience and are the result of a process of abstraction.
However, Stumpf clearly distinguishes the question of the origins of
concepts, belonging to descriptive psychology, from the question of
the origins and justification of knowledge, which falls within the
theory of knowledge. This distinction is at the heart of his
habilitation thesis and we shall have the opportunity to return to
this important issue.



From these two main classes, Stumpf distinguished within his
classification three neutral sciences whose task is to study the
structure of the contents of psychical functions and sense phenomena
in general. Stumpf claims that they represent three different fields
of research, corresponding to three distinct sciences: phenomenology
as the science of phenomena, eidology which studies formations, and
the general theory of relations understood as the science of relations
as a whole. These three new sciences are said to be
"neutral" with regard to existing sciences and they are
"propaedeutic sciences" in that their field of study
represents the raw material and the starting point of the natural
sciences as well as the social sciences. To use Stumpf's terms,
they are the *atrium* and the *organon* of all sciences
and of philosophy.



What he calls phenomenology in his two Academy treatises of 1906 is a
field of study to which he dedicated many works, from his early work
on the origins of space perception up to his 1926 book on vowels and
phonetics. The field of phenomenology in Stumpf's sense is
limited to phenomena and their properties and is defined narrowly as
the science of phenomena. The study of formations and of objects of
thought in general belongs to the second neutral science which Stumpf
calls "eidology," an expression that he borrowed from
Herbart. Stumpf first introduced the notion of formation
(*Gebilde*) in 1902 in order to characterize the specific
contents of functions or what he also calls the objective correlates
of a psychical function. Formations are contents that enter into
consciousness through carrying out specific functions in the sense
that to every class and subclass of acts there corresponds a certain
content specific to each and every act. All psychical functions, from
the simplest to the most complex, have their specific contents:
concepts, states of affairs and values, to name only the most
important. For example the act of abstraction, which is responsible
for the formation of concepts, notably the concept of space, has a
concept as its own specific content. States of affairs are contents of
judgment, and they are comparable to Meinong's
"objectives", Husserl's "objectivity" or
to Bolzano's "proposition in itself"; they play a
central role in Stumpf's logic as we shall see later. (G.
Frechette, 2015; A. Chrudzimski, 2015) These are
"correlates" of thought and, in contrast to individual
acts, they have an objective character. The objectivity of formations,
however, is not to be understood in terms of intentional inexistence
(Brentano) or in the sense of Platonic realism (Bolzano and Frege),
because any formation is logically dependent of the act that produces
it, and the existence of states of affairs is logically linked to that
of the act of judgment. They are therefore abstracted in the sense
that they cannot *exist* independently from the acts by which
they are produced. The same rule can be found in the field of more
complex functions such as emotions, desires, and voluntary actions,
whose specific contents are values. The very possibility of a neutral
science such as eidology shows that we can study values in themselves,
independently of any function; yet Stumpf claims that it is not
possible to dissociate formations from their original functions.



Relations form the group of objects whose study belongs to the general
theory of relations. This theory represents an important part of logic
and formal ontology, and its task in fact lies in the study of the
laws governing the formal relations between objects and parts of
objects. This aspect of the general theory of relations is comparable
to Husserl's pure logic. The relations of structure between
psychical functions and the hierarchy within the domain of simple and
complex functions obey what Stumpf refers to as the "laws of
structure" between parts or aspects of a whole. Its task is to
establish relations between phenomena, functions, and formations and
to investigate the origins of complex relations in simple relations,
fixed by means of definition, and to determine the structural laws to
which they obey. To these *Grundverhalnisse* or
fundamental relations belong, namely, the concepts of analogy,
equality and fusion that Stumpf examines succinctly in the second
volume of *Tonpsychologie*, as being the relations of logical
and real dependency, the part-whole relations as well as the relations
of real dependency between psychical functions. These relations are
immanent to phenomena and are noticeable directly and without
intermediary. Sensory contents are noticed or remarked in themselves,
and each of these relations is, to again use the Scholastic
expression, an *ens rationis cum fundamento in re*. The notion
of fusion designates one of the forms of relations that structure the
sensory material. It is defined as the relation between two phenomena
(or contents of sensation) by virtue of which they do not merely form
a sum, but a whole. Stumpf argues that the elements which fuse into
the whole, for example quality and intensity of sounds in a melody,
are not changed, but this relation of fusion establishes between these
contents a narrower unity which is perceptible as a Gestalt. To use
the well-known case of the melody, moments of quality and of intensity
form in that case a unitary whole which is perceptible as a
"quality of form," and it is precisely the unitary
character of this perception, the fact that it is perceptible in one
stroke and immediately as unitary form, that Stumpf tries to account
for with the aid of the notion of relation of fusion.


## 5. Philosophy and Metaphysics



Within this classification of sciences, philosophy is meant to be the
ultimate science responsible for the issues common to all sciences,
i.e. to the natural and human sciences as a whole, but which are not
specifically handled by any *per se*. That is why philosophy is
considered the most general science of all sciences, and is defined
"as the science of the most general laws of the mental and of
those of reality in general" (Stumpf, 1906a, p. 91). Stumpf
reiterates this position in his autobiography:



> 
> However one may formulate the difference between mind and nature,
> everybody distinguishes them in some manner. The philosopher, however,
> looks for what they may have in common. Thus philosophy is primarily
> the science of things in general, or metaphysics, to which the gateway
> is epistemology. But if philosophers since olden times have generally
> regarded psychology as belonging to their proper field is due to the
> fact that psychical elements have been much more prominent than the
> physical in forming fundamental metaphysical conceptions. It is
> therefore to the point to define philosophy as the science of the most
> common laws of the psychical, and of the real in general (or
> conversely). This is the only way through which we can justify the
> inclusion of logic, ethics, aesthetics, the philosophy of law,
> pedagogy, and other branches in the domain of the philosophical
> sciences; the connecting link is always essentially psychology, which
> must not therefore forget - when absorbed in experimental detail
> - the nobler phenomena of mental life that cannot be
> investigated in this manner and the great general questions. (Stumpf,
> 1924, p. 414-415)
> 



Philosophy thus understood is first philosophy insofar as its main
task is to investigate the laws that provide the cohesion and unity
between mind and nature. It is closely related to metaphysics or to
what Stumpf also calls "metapsychics" to the extent that
it presupposes psychology as much as physics. But unlike traditional
metaphysics, which is thought of *a priori*, Stumpf's
view of metaphysics, as he repeatedly imparted since his first
lectures on metaphysics in Wurzburg, is based on experience
insofar as it is continuous with the empirical sciences and proceeds
inductively, i.e. according to a bottom-up approach. (D. Fisette,
2015c)



Stumpf's contribution to metaphysics has been the subject of
recent studies, (K. Schuhmann, 1999; D. Jacquette 2000-2001; R.
Rollinger, 2008b; R. Martinelli, 2011, 2015) and his lectures on
metaphysics delivered in Halle in the late 1880s has been recently
published. (C. Stumpf, 2015) He distinguished following Brentano four
main branches of metaphysics: transcendental philosophy, which focuses
on the justification of our knowledge of the external world, ontology
whose domain includes, in addition to the categories, the topic of
psychophysical relations and that of causality among other things;
thirdly, theology which is concerned with the evidence of the
existence of a foundation of the world, and finally, cosmology which
deals namely with issues related to the actual infinite.



Stumpf focuses particularly in his writings on two specific topics
related to the domain of ontology (D. Jacquette, 2000-2001, R.
Martinelli, 2015), namely the categories and psychophysical relations.
In *Erkenntnislehre*, he examines the categories of thing
(substance), cause, necessity (legality), truth, reality, equality,
and number (Stumpf 1939-1940, p. 13) and claims that these
*Grundbegriffe* or categories have their origin in (internal
and external) perception. This is primarily the case for the concept
of necessity which is at the heart of his critique of psychologism.
Stumpf agrees with Hume and J. S. Mill that we cannot observe
necessary relations in nature, but he argues that internal perception
provides us with many cases of necessary relations such as
mathematical axioms, or in the perception of three consecutive sounds
where one of them is necessarily intermediate (as to the pitch)
between the other two. (Stumpf, 1939, p. 48) The concept of necessity,
as the concept of causality, is formed through a process of
abstraction and can then be used, hypothetically, to explain natural
events based on causal laws. Moreover, we also find in Stumpf an
original account of tropes which influenced the young Husserl. (R.
Rollinger, 2015)



The second metaphysical topic to which Stumpf attaches great
importance in his writings is that of psychophysical relations. Unlike
most of his contemporaries, including Brentano and Husserl, Stumpf
unequivocally rejects the doctrine of psychophysical parallelism
according to which the physical and the psychological are aspects of
one and the same reality and advocates, following Lotze, a form of
interactionism that rejects monism in favour of dualism. The position
that Stumpf defends in "Leib und Seele" and in his two
studies on Spinoza, may be summed up by the following excerpt taken
from his posthumous book:



> 
> The discredited dualism however, according to which everything in the
> world, including the mental and physical, stands in thoroughgoing
> interaction (directly or indirectly), now appears as the true monism.
> According to interactionism, the world, despite the diversity of its
> parts, is a unified organic whole. Thus the parallelistic view proves
> to be impractical and contradictory, and the theory of interaction
> therefore remains, for the time being, the best guide through the maze
> of this great problem. (Stumpf, 1939-1940, p. 822)
> 



One of Stumpf's arguments in favour of interactionism and
against parallelism is Darwin's theory of evolution (Stumpf,
1910, p. 78-79) to which he attaches great importance since the
1880s (E. Valentine, 2000) In an article entitled "Der
Entwicklungsgedanke in der gegenwartigen Philosophie,"
Stumpf compares the bearing of Darwin's theory on science to
that of the Copernican revolution in astronomy. (Stumpf, 1899a)
Stumpf's interest in Darwin's theory is clearly expressed
in his work on psychophysical relations, the origins of music, animal
psychology as well as in those on child development.



In his lecture on metaphysics as in his paper "Leib und
Seele," Stumpf's main target is Mach's phenomenalism
and neutral monism, which amounts to reducing physical objects and
subjectivity to functional relations between sensations (or elements)
and inevitably leads, according to Stumpf, to idealism and solipsism.
Stumpf published in 1919 a very interesting study on Spinoza's
parallelism in which he proposes an original and unorthodox
interpretation of Spinoza's *Ethics*. He argues that
Spinoza's parallelism, if understood correctly, has nothing to
do with the psychophysical parallelism which was dominant at that time
since Fechner. According to Stumpf, the heart of Spinoza's
parallelism rests on the distinction between act (or mental state) and
the immanent object towards which it is directed. (Stumpf 1919b, p.
19) This act-content parallelism has its source in Aristotle and has
been inherited by Brentano and Husserl *via* many philosophers
from Thomas Aquinas to Descartes and Spinoza. Stumpf argues that this
interpretation is consistent with Spinoza's pantheism insofar as
the distinction between the act and its immanent content has been
transposed to God in Spinoza's *Ethics*. For since
God's intellect is considered by Spinoza as the only possible
subject, intentional acts and contents are then necessarily two of his
numerous modes or attributes. (see R. Martinelli, 2011) Despite his
critique of psychophysical parallelism, Stumpf advocates, like
Spinoza, a form of pantheism that is consistent with his deterministic
and mechanical conception of nature. In *Erkenntnislehre*,
Stumpf recalls that pantheism is a view that he adopted in 1876 in the
course of several discussions with Brentano on theism and this was the
position that he already advocated in his lectures on metaphysics in
Wurzburg and later in Halle. Stumpf's main argument against
theism is its inability to satisfactorily resolve the problem of evil
in the world. However, as Stumpf pointed out in
*Erkenntnislehre* (1939-1940, p. 681, 798, 17), in his
last writings, Brentano seems to adopt a form of pantheism similar to
that of Spinoza. (Stumpf, 1939-1940, p. 798)


## 6. Philosophy of Mathematics



The recent publication of Stumpf's habilitation thesis
*Uber die* *Grundsatze der Mathematik* raises
many questions which have been the subject of recent commentaries. (D.
Munch, 2002-2003; W. Ewen, 2008; C. Ierna, 2015).
Stumpf's habilitation thesis focuses on the nature and origins
of mathematical principles or axioms. Its starting point rests on the
following question:



> 
> Is there knowledge of scientific importance, which is in no way based
> immediately nor mediately on experience; and if there is such
> knowledge, what is its source? (Stumpf, 2008, Bogen 1-1)
> 



The habilitation thesis is divided into two parts. In the first part,
Stumpf examines two antagonistic positions which prevailed at the
time, namely J. S. Mill's empiricism according to which there is
no knowledge that is not mediately acquired by induction, and Kantian
transcendentalism which claims that our knowledge of the general
principles of mathematics is based on synthetic *a priori*
judgments. Stumpf rejects both accounts and seeks to show, in the
second part of his thesis, that axioms and mathematical propositions
are analytic *a priori*; they are not acquired through
experience but are the result of a process of deduction from
concepts.



In the critical part of his work, Stumpf raises the problem of the
origins of the laws and principles of logic and mathematics as
follows: if these principles are inductive in nature, as Mill believes
them to be, then they do not constitute necessary truths; if, on the
contrary, they are necessary truths, then the question arises as to
whether they are synthetic *a priori* judgments as Kant claims
or analytic *a priori* propositions as Stumpf claims. Against
Mill, Stumpf argues that the axioms are not the result of empirical
generalization based on an inductive process, and that arithmetic,
like geometry, is a deductive science based on *a priori* and
necessary truths, which are justified by the evidence of internal
perception. (Stumpf, 2008, Bogen 5-4) Stumpf therefore agrees
with Kant that axioms are necessary truths, but he denies that they
are based on synthetic *a priori* judgments. Stumpf argues
rather that Kant's synthetic judgments presuppose a kind of
"mental machinery" (Stumpf, 2008, Bogen 16-3) in
order to account for their formation, as they involve numerous
assumptions, notably the *a priori* forms of sensibility,
intuition, and *Denkformen*, which Stumpf takes to be mere
constructions. Stumpf criticizes Kant especially for the thesis
according to which the origins of the necessity of our knowledge of
axioms lie in intuition, in that knowledge of mathematics then becomes
dependent upon experience. However, Stumpf argues that intuition
understood in the Kantian sense is inductive and only leads to
concepts and never to propositions. That is why Stumpf claims that the
very idea of synthetic *a priori* judgments is a contradiction
in terms. Axioms and propositions are analytic judgments constructed
deductively from concepts. We can see that Stumpf's fundamental
argument against empiricism and transcendental criticism rests on the
fundamental distinction between concept and proposition, which are of
major philosophical significance in Stumpf's subsequent work on
the theory of knowledge, as we will later see. In his habilitation
thesis, Stumpf is more concerned with delimiting the field of logic
and mathematics from that of psychology. In this regard, Stumpf
clearly separates the question of the origins of concepts, which is a
psychological question, from the logico-mathematical domain to which
propositions and axioms belong. For, as Stumpf argues in his
posthumous work, one can agree with empiricism on the psychological
origin of concepts while acknowledging that there is *a priori*
knowledge which is independent from experience. (Stumpf,
1939-1940, p. 126) For Stumpf admits that the basic concepts of
arithmetic (the concept of number) and geometry (the concept of space)
have their origins in experience. In his *Raumbuch*, published
three years after his habilitation thesis, Stumpf attempts to
demonstrate the thesis that the concept of space has psychological
origins. However, the position one takes on this issue is distinct
from that which one adopts regarding the nature of propositions and
necessary truths in the logico-mathematical domain. For, in this
domain, one is solely concerned with axioms and propositions, which
can be deductively inferred, and one also assumes the origins of the
axioms and their justification as necessary truths. Stumpf argued in
1870 that these axioms are analytic *a priori* propositions and
that arithmetic and geometry are deductive sciences.



There is a remarkable continuity in the work of Stumpf regarding his
positions from his habilitation thesis up to his posthumous work, not
only on the foundation of mathematics but also on the theory of
knowledge. One of the main theses he advocates in
*Erkenntnislehre* is based on the distinction between the
origins of concepts and the origins of knowledge. (Stumpf,
1939-1940, SS 1) Stumpf revisits the theme of mathematical
axioms (Stumpf, 1939-1940, SSSS 12-13) in the
context of a critical discussion of Husserl's doctrine of formal
and regional ontologies. Stumpf's conception of the concept of
number in *Erkenntnislehre* is the same as the one he advocated
in his habilitation thesis and in his Halle lectures, and
Stumpf's position is very similar to that of Brentano and his
students. (W. Ewen, 2008, p 162 f.; C. Ierna, 2015) In this regard,
Stumpf's influence on his student Husserl's habilitation
thesis regarding the origins of the concept of number, including
Husserl's conception of symbolic presentations, is to be
considered. (D. Munch, 2002, pp. 31-37)



Now, what is the place of mathematics in Stumpf's classification
of sciences? This question was left open in our earlier remarks
because the classification criteria we used were based on the cardinal
distinction between phenomena and psychical functions, which underlies
the main division between natural and social sciences. But as Stumpf
pointed out in his paper "On the Classification of
Sciences", contrary to the method with which most
classifications that are meant to be normative proceed, a
classification that describes the state of a science as it is
practiced at a given time in the history cannot rely on a single
criterion of classification, and its task is to show how several
criteria are intertwined in many ways (C. Stumpf, 1906a, p. 88). This
is why one must rely on a new criterion based on the distinction
between *a priori* and *a posteriori* methods in order
to delineate mathematics, including geometry, from the other sciences.
Indeed:



> 
> The most tangible characteristic that is offered to us to delineate
> the mathematical sciences from all other sciences is that of the
> differences in method, i.e. the *a priori* method as opposed to
> the *a posteriori* method. Despite the opposing effort to
> assimilate mathematics to the natural sciences, this distinction
> persists, and in my opinion, rightly so. The attempt made by J. St.
> Mill to inductively derive the principles of mathematics (and logic)
> from a collection of several individual experiences manifestly runs in
> circles. (C. Stumpf, 1906a, p. 65)
> 



This applies *a fortiori* to geometry which Stumpf, unlike
Kant, refuses to ground on the concept of intuition insofar as it is
an analytic *a priori* science, like any other branches of
mathematics. The position he advocates in 1906 is therefore not
different from the one he advocated thirty-five years earlier in his
habilitation thesis. (Ewen, 2008, p. 157ff.) As an *a priori*
science, one could say that mathematics is actually presupposed by all
other sciences as Stumpf suggests in referring positively to Auguste
Comte's hierarchy of the positive sciences. (C. Stumpf, 1906a,
p. 88) For, according to Comte, the hierarchy between sciences within
his classification presupposes that all sciences, from physics to
physiology, logically depend on mathematics, that is, the most simple
science, and is the most autonomous with regard to all other sciences.
In this regard, Stumpf here adopts a position akin to that of Brentano
who followed Comte's criteria on the matter of the
classification of sciences, with the important difference being that
psychology replaces sociology within Brentano's system of
sciences and that the field of psychical functions is, according to
Stumpf, independent from all other sciences. (D. Fisette, 2015d;
2018b)


## 7. Theory of Knowledge



The theory of knowledge occupies a central place in Stumpf's
philosophy in his later works, especially in *Erkenntnislehre*,
and we know that this discipline has always been at the heart of his
teaching up to the end of his career in Berlin. We saw that Stumpf
associates it both with the neutral sciences and the foundation of
knowledge, specifically with the ultimate justification of knowledge.
(Stumpf, 1939-1940, p. 7, 124) One of the central questions of
the theory of knowledge is psychologism, which is the main topic in
Stumpf's article "Psychology and the Theory of
Knowledge." (D. Munch, 2002; G. Frechette, 2013)
Stumpf advocates a form of critical realism that he specifically
opposes to Kantian idealism, and which maintains that the outside
world is always the object of a supposition or hypothesis. Moreover,
he claims that the only material that we have for formulating such an
hypothesis are the concepts drawn from experience that enable us
"to calculate the course of events." One of the main tasks
of the theory of knowledge, therefore, is to account for the most
general modes of knowledge of the outside world. (Stumpf, 1891, p.
503) Stumpf distinguishes the theory of knowledge as a field of study
from that of psychology on the basis of the cardinal distinction
between the domain of concepts and that of propositions or necessary
truths, as elaborated in his habilitation thesis.



Inquiry on the origins of concepts, as we said, is a task specific to
psychology. In contrast, the theory of knowledge is limited to the
research and justification of "the most general and immediately
evident truths" (Stumpf, 1891, p. 501), such as laws and axioms
necessary for knowledge. Yet, these axioms are nothing but
propositions that we assume to be true and necessary, and they have
their origin in the content of a specific class of psychical
functions, namely judgments. Since the contents of judgments are
formations or products (*Gebilde*) which, as we said, belong to
eidology, the field of research of the theory of knowledge is
therefore linked to that of this neutral science which also includes
states of affairs. One must therefore avoid confusing the question
pertaining to the nature of axioms with that of the psychological
origins of concepts, but one can no more entirely separate the theory
of knowledge from descriptive psychology since axioms are originally
the contents of a specific class of psychical functions, i.e. the
contents of judgments or of propositional attitudes whose
justification is the task of the theory of knowledge. (Stumpf, 1891,
p. 495-496; 1939-1940, p 124)



In light of this distinction, one can better understand the
significance of the debate on psychologism such as Stumpf describes it
in his 1891 paper. Stumpf opposes two schools of thought on the
question of the relationship between the theory of knowledge and
psychology: Kantian criticism that dissociates the theory of knowledge
from psychology, and psychologism which Stumpf defines in this paper
as "the reduction of all philosophical investigation, and
especially all epistemological investigations, to psychology."
(Stumpf, 1891, p. 468) The argument in favour of psychologism boils
down to the idea that "knowledge is itself a mental process and
accordingly the study of its conditions would be a psychological
investigation." (Stumpf, 1891, p. 468) Critics of psychologism,
on the other hand, argue that a psychological investigation can never
lead to "knowledge of general and necessary truths."
(Stumpf, 1891, p. 469) Now since the conditions of possibility of
knowledge, i.e. the forms of intuition and thought, are themselves
*a priori* and therefore not analysable (Stumpf, 1891, p. 493),
psychology is therefore useless for Kantian criticists.



The position adopted by Stumpf in this debate consists in conceding to
criticism that necessary truths are irreducible to facts while
admitting, with psychologists, that psychology is essential to the
theory of knowledge. Hence the main mistake he attributes to
Kantianism, which consists in refusing the assistance of psychological
research in the theory of knowledge. (Stumpf, 1891, p. 493, 500) The
field of psychology is understood here in a sense that is broad enough
as to include sensory phenomena and mental functions because, in 1891,
Stumpf did not explicitly distinguish the field of phenomenology from
that of descriptive psychology. Now the main criticism he addresses to
Kant focuses on the dichotomy between form and matter, and it is
primarily the Kantian doctrine of phenomena (the manifold of
intuition) that he holds responsible for its most obvious
"mistakes." In this article, Stumpf reiterates the main
criticism that he addressed to Kant in his *Raumbuch*, namely
"the doctrine of space as a subjective form and the Kantian
conception of sensations as amorphous and unstructured matter designed
to support the synthetic and unifying activity of the
understanding." (Stumpf, 1873, p. 15 f.)



However, this criticism of the Kantian theory of knowledge does not
make Stumpf an advocate of psychologism. For Stumpf acknowledges with
critical philosophy that we must maintain a strict concept of
necessity and thus oppose the reduction of the principles and laws of
logic and of science in general to simple empirical generalizations.
Stumpf here refers explicitly to J. S. Mill, and maintains that the
laws of nature and the principles of logic such as the principle of
non-contradiction, for example, cannot be obtained merely by induction
and are irreducible as such to the process of empirical generalization
or "an accumulation of observations." (Stumpf, 1891, p.
499-500) This raises the question as to what is the relationship
between the position adopted by Stumpf in his 1891 article on the
debate on psychologism and the position adopted by Husserl and Frege
on the same issue several years later. Munch (2002, p. 50) argues
that Stumpf's position not only comes close to that of Husserl,
but it also constitutes the background of Husserl's critique of
psychologism in his *Logical Investigations*. Ewen (2008, pp.
13, 22) argues instead that Stumpf is closer to the
anti-psychologistic positions of Frege. But since they do not provide
a clear definition of what is meant by "psychologism" and
do not clearly present Stumpf's, Frege's, and
Husserl's respective arguments against psychologism, there is no
way to settle this debate at the moment. (D. Fisette, 2015a)



That being said, there are parallels that can be drawn between the
positions of Stumpf and of Frege on the foundations of mathematics and
on psychologism. (see W. Ewen, 2008, p. 97 f.) Several attempts have
been recently made to explain these parallels, and these accounts all
focus on their mutual relationship with Lotze during their stay in
Gottingen in the early 1870s, while Stumpf, after his
habilitation, was Privatdozent (1870-1873), and Frege pursued
his studies in mathematics (1871-1873). Although it can be
assumed that the two philosophers met during this period, we have no
written evidence that confirms this. (W. Ewen, 2008, p. 97 f.)
Historical testimony does not say whether Frege attended
Stumpf's lectures in Gottingen on Aristotle's
metaphysics, which he taught for three consecutive years, or his
lectures on "inductive logic with a particular focus on the
problem of natural science" that he taught during the summer
semester of 1873. Nevertheless, the correspondence that Frege and
Stumpf exchanged in the early 1880s seems to testify that the two
philosophers knew each other. In any case, an explanation of the
elective affinities between Stumpf and Frege might be found in the
work of Lotze. (Stumpf, 1918, p. 7; D. Fisette, 2015a)


## 8. Logic, Language, and States of Affairs



Stumpf did not publish any specific work on the topic of logic and
wrote only a few pieces on language. These are however two topics in
which Stumpf was very much interested. The topic of language was
central in his 1876 paper on Anton Marty's dissertation entitled
*Uber den Ursprung der Sprache* (A. Marty, 1875; L.
Cesalli, 2015). Also worth mentioning is an essay on the psychology of
music in England (1885) and his book *Die Anfange der
Musik* (1911) in which he discussed, in relation to Spencer and
Darwin, the thesis of the linguistic origin of music. Finally he made
a significant contribution to the field of phonology and conducted an
extensive research on the nature of vowels and linguistic sounds, and
this led to the publication of his book *Die Sprachlaute*
(1926) in which he experimentally confirms Helmholtz's
principles on the theory of vowels. As to the domain of logic, there
are many syllabi and extensive lecture notes, including those written
by Husserl during his studies in Halle, which again show a direct
influence from Brentano (K. Schuhmann, 1996, 1997; R. Rollinger,
2015). We know that logic is closely related to Stumpf's theory
of relations and eidology, which are central in both his philosophical
and empirical works. More precisely, his contribution to logic in
these two research areas concerns in fact the specific content of
judgment (belief) or what he also calls states of affairs, and that
part of the theory of relations pertaining to part-whole relations.
The first leads to a theory of the states of affairs while the second
was useful in developing a formal ontology, one that was central in
the logic of his student Husserl. Finally, mention should be made of
Stumpf's publications on the relationship between logic and the
theory of probabilities, and his research pertaining to the
elaboration of a theory of induction. He claimed that the application
of probability concepts does not involve any presuppositions about the
external world and the law of causality, for the calculus of
probability is purely *a priori* and is solely derived from the
concept of probability itself.



Regarding his lectures on logic, while he accepted Brentano's
important distinction between what a statement expresses and what it
means, he did not subscribe to Brentano's central thesis on the
reduction of categorical to existential statements. The meaning of a
sentence corresponds to the content of a function, and it is distinct
from the quality and matter of a predicative judgment. The quality of
an act of judgment consists in its affirmation or negation, its
acceptance or rejection of the matter of a judgment expressed
linguistically by the copula "is" or its negation. The
matter (*Materie*) of a judgment, which is provided by the
lower level act of presentation, is what remains when one disregards
the affirmation and negation, i.e. the simple complex of presentation
(subject and predicate minus the copula). In addition to its quality
and matter, a judgment has a content and a state of affairs, the
latter roughly corresponding to what we call a proposition. Stumpf
conceives a state of affairs both as a specific content of judgment
and as its objective and necessary correlate, which is expressed
linguistically in "subordinate clauses" or in the form of
a "substantivized infinitive." It therefore corresponds to
what Stumpf called axioms. The truth of a statement is defined as the
correspondence of the judgment quality to its content, that is, the
property of a judicative content by virtue of which acceptance (or its
opposite, rejection) is prompted by purely objective motives. This
concept of truth is grounded in the evidence of internal perception
(is true what is mediately or immediately self-evident), which also
plays a central role in his theory of knowledge.



The study of the structures of the contents of judgment as such, apart
from its functions and contingent states, is one of the tasks Stumpf
assigns to this part of eidology which he calls the theory of states
of affairs. (A. Chrudzimski, 2015) One of Stumpf's original
contributions to logic rests on the notion of state of affairs, which
was already used in the history of philosophy and especially by Lotze.
(B. Smith, 1989, SS 2) Stumpf already used this notion in his
lectures on logic in 1888 (Q 13, p. 4), and it is now well-known that
it has been subsequently taken over by many philosophers including
Husserl and Wittgenstein. In 1906, Stumpf associates it with the
concept of formation or product (*Gebilde*) and applies it to
both intellectual and emotional functions, where in the latter case it
is conceived as a value (also called *Wertverhalt*) on which
ethics and practical philosophy in general are based. These
*Gebilde* are objective entities that are related both to the
concept of objective in Meinong, to that of objectity in Husserl, and
to Bolzano's concept of "proposition in itself."
(Stumpf, 1906b, p. 30) For this student of Lotze, the doctrine of
*Gebilde* is not incompatible with the Platonic theory of ideas
though "without its metaphysical conclusions." (Stumpf,
1906a, p. 33) One can certainly entertain a formation such as a state
of affairs without having it as an actual content of judgment, but it
is then a mere abstraction. Because, says Stumpf, "the state of
affairs cannot be immediately given for itself independently of any
mental function, and therefore effectively. It can only be real as the
content of a judgment that is actually taking place. [...] So,
functions (and indeed only the conscious functions which are properly
present) are facts immediately known, while the *Gebilde* are
facts only regarded as contents of functions." (Stumpf, 1906a,
p. 32) Objectivism is an important issue in Stumpf's philosophy
since it serves as one of his main arguments against psychologism.



States of affairs are, as any other formation, governed by general and
necessary laws, and are independent of the individual and the
contingent act of judging. These structural laws or axioms as he calls
them in his *Erkenntnislehre* govern relations between
elementary psychical formations. Stumpf distinguishes between formal
axioms, which apply to any objects, and material or regional axioms
which belong to specific domains of objects such as the domain of
phenomenology (structural relations between phenomena) and that of
psychology (structural relations between elementary psychical
functions). Of particular interest to logic are the axioms of
consequence (*Folgerungsaxiome*), which are expressed in
propositions and which establish a relation between the premises and
the conclusion in terms of necessary inference.


## 9. Further Contributions


### 9.1 Ethics



In his second address as rector of the University of Berlin in 1908,
Stumpf (1910c) expressed his opposition to formalism and moral
skepticism and argued for an ethics based on an objective theory of
values. It will be recalled that values are specific contents of acts
belonging to the class of emotional functions or feelings and that
they resemble the contents of judgment that belong to the class of
intellectual functions. Ethics, like aesthetics, is grounded entirely
on the class of feelings. Echoing Lotze's distinction between
passive and active feelings, Stumpf argues that emotions are passive
feelings as opposed to active feelings which are directed towards a
duty, a project, or an intention to be achieved through voluntary
actions. Values or value-feelings, which are essential for an ethics
worthy of this name, refer to the specific contents of will or
voluntary actions. Moral actions, as opposed to instinctive or
mechanical behavior, presuppose knowledge since this class of acts is
grounded on judgments that in turn are at the foundation of
theoretical knowledge. Just as true judgment, moral behavior differs
from blind actions by the insight or self-evidence that is to the
content of a feeling (value) what theoretical self-evidence is to a
state of affairs. And just as the truth in logic, goodness or what is
worthy of being wanted or desired is based on intrinsic and objective
values that are immune to any external forces.


### 9.2 Musicology and Aesthetics



In the general field of musicology, in addition to his numerous
studies on acoustics, which for the most part have been collected in
his *Beitrage zur Akustik und Musikwissenschaft*, and his
book of 1926 *Sprachlaute* (cf. B. Pompino-Marschall, 2003),
those on ethnomusicology (cf. G. Schworer-Kohl, 2011), published
in his *Sammelbande fur vergleichende
Musikwissenschaft*, whose fourth volume contains the study on
Romanian folk music by the famous composer Bela Bartok
(1922-1923; V. Lampert, 2008), we owe to Stumpf several studies
on the history of music. (Stumpf, 1885, 1896, 1897, 1911) In his
autobiography, Stumpf listed his work in this field and stressed the
importance of his contribution in two of his works:



> 
> To the systematic science of music belong, besides my works on
> physical and psychological acoustics, especially the treatise,
> *Psychology of Music in England*, and the book about the
> beginnings of music. In the treatise, which is an introduction to the
> later works on *Tonpsychologie*, I discussed the relation of
> music to language, and that of human speech to the utterances of
> animals - with reference to Spencer and Darwin - but also
> the exaggerated nativism of Gurney (power of sound), who practically
> ignored all genetic explanations and focused only on the erotic
> feelings of animal ancestors. (Stumpf, 1924, p. 438-439)
> 



His classic work, *The Origins of Music*, made known notably by
the famous anthropologist and linguist Edward Sapir (1912) thanks to
his positive review of this work in 1912, has recently been published
in English. (see E. M. von Hornbostel, 1933; M. Muller, 2003; A.
Simon, 2000; H. de la Motte-Haber, 2011) This book is the culmination
of more than twenty five years of empirical and theoretical research
in the field of musicology and is divided into two main parts: the
first, entitled "The Origin and Archetypes of Music
Making" deals with the theoretical aspects of the debates at the
time on this issue. Three theories on the origin of music are
discussed, namely that of Darwin, that advocated independently by
Rousseau, Herder, and Spencer, and finally that of Wallaschek and K.
Bucher. All these theories are rejected in favour of that
proposed by Stumpf in the second chapter entitled "The Origin
and Archetypes of Singing." Stumpf's theory is based
mainly on the famous concept of fusion that he developed in his
*Psychology* *of Sound*. The third chapter entitled
"Primitive Instruments and their Influence" traces the
history of musical instruments among primitive peoples. In Chapter IV
"Polyphony, Rhythm, and Intoned," Stumpf examines the
music of primitive peoples with regard to the forms of polyphony,
rhythm, and the relation between song and speech. (see Deutsch, Sommer
and Willam, 2003) The last chapter "Paths of Development"
consists in a study of the different stages of the development of
music. The second part of the book, "Songs of Primitive
Peoples" is a study of music among primitive peoples in
different countries of the world, and is based on several songs of
which Stumpf offers the transcription and a detailed musical analysis.
(H. Gunther, 2003)



Moreover, although Stumpf has devoted only one article specifically to
the theme of aesthetics, this topic is raised very frequently in his
work, namely in his book *Gefuhl* *und
Gefuhlsempfindung* which includes three of his papers on
emotions and sense feelings (Stumpf, 1928b**;** C.
Allesch, 2014, 2003). This issue led to a long discussion in his
correspondence with Brentano on whether pleasure, and aesthetic
pleasure procured by a work of art, is intentional or phenomenal in
nature. In his article "Aesthetic Enjoyment and Tragedy,"
Stumpf summarizes the problem of aesthetics as follows:



> 
> Every work of art bears within itself its primary purpose [which
> consists] in the production of an aesthetic enjoyment. And here, in
> this immediate effect, lies the enigma. (Stumpf, 1910a, p. 5)
> 



This action or effect (*Wirkung*) of the artwork is immediate
in a way comparable, for instance, to the experience that we have of
pain, and is independent of any difference in culture, specialized
knowledge of contemplated objects or worldview (historical, cultural
or other). Stumpf acknowledges that sensations can act aesthetically
on a subject without any conceptual thought or representation.
However, the full aesthetic sentiment is forced upon us when and only
if sensations and combinations of sensations "are entangled in
an act of relational thinking." That is to say, "an
aesthetic affect presupposes a judgment on a state of affairs, on a
fact." (1899, p. 8) The feeling of pleasure is immediately
linked to an activity as sensory pleasure to sensations, but it is not
yet an emotion in the strict sense. For there to be an emotion in the
experience of enjoyment (*Entzucken*) of a work of art,
the relations intuited in a unitary and immediate way must become an
object of consciousness, and therefore an intentional object. Hence
the dual origin (or source) of aesthetic experience: the first is what
he calls the fullness (*Fulle*) of the formal relations
among the parts of a true work of art, while the second is derived
from the properties of the object or, more precisely, the state of
affairs. (Stumpf, 1899, p 8; 1924, p 54) The first source is
phenomenological and resides in the formal relations which are given
directly to consciousness. The second source is more complex in that
it presupposes the processing of the phenomena and sensory data
through judgment. (Stumpf, 1926, p. 2-3) These two sources,
however, form a unitary content that can only be distinguished by
abstraction.



The works and teachings of Stumpf in the field of emotions have had
some influence on the literary work of the young Robert Musil. We know
that Musil went to Berlin in 1903 to undertake his studies in
philosophy, physics and mathematics. In 1908, he successfully
defended, under the direction of Stumpf, a doctoral thesis on the work
of Ernst Mach (R. Musil, 1908; R. Haller, 2003). Another important
aspect of their relationship concerns Stumpf's influence on
Musil's literary work, which gave rise to a vast literature. One
of the important sources of Musil's early novels and theoretical
fragments is the work of Traugott K. Oesterreich (1910) who wrote his
doctoral dissertation in 1905 under the supervision of Stumpf. Another
source is Stumpf's theory of emotions, which he presented in his
articles of 1899 and 1907 (Stumpf, 1928b) and his lectures on
psychology given during the winter semester of 1906-1907 in
which he attaches great importance to the theme of sense feelings and
emotions. It is more than likely that Musil attended these
lectures.


### 9.3 Empirical Psychology



Stumpf's scientific contribution to the field of empirical
psychology has been in recent years highlighted by several studies. In
addition to the numerous studies that explore Stumpf's
relationship to psychologists such as Kulpe (W. Baumgartner,
1997), Herbart (M. Kaiser-El-Safti, 2009, 2010, 2011; S. Poggi, 2014),
Helmholtz (H.-P. Reinecke, 2003) Wundt (U. Wolfradt, 2011), or to H.
Ebbinghaus (see U. Wolfradt & M. Kaiser-El-Safti (eds.), 2010),
several other studies have highlighted Stumpf's diversified
contribution to several sub-disciplines of psychology, including the
psychology of sound, Gestalt psychology, animal psychology, the
psychology of child development, etc. Stumpf's most important
contribution in the field of psychology - understood in the
narrow sense of the science of psychical functions - is his
*Psychology of* *Sound* published in two volumes.
(Stumpf, 1883, 1890) The first volume deals with individual sound
judgments while the second, dedicated to Brentano, studies the
consciousness of simultaneous sounds. According to his initial
proposal, Stumpf's project was to write two more volumes. The
third was to focus on musical phenomena such as consonance,
dissonance, accords, melodies, etc., while he had planned to study
feelings generated by sound (*Tongefuhle*) in the fourth.
Part of his research on these issues was published separately in his
*Beitrage zur Akustik und Musikwissenschaft* (9
volumes).



This complex and unfinished work attracted much interest at the time
and was reviewed by philosophers such as Meinong and Natorp and by
psychologists such as J. Sully, H. Ebbinghaus, and especially W. Wundt
who, in his anonymous review of the first volume of the book,
criticized Stumpf's method and the hypothesis of the relativity
of sensations to judgment. (see C. Allesch, 2003) Let us recall,
however, that this book is not a phenomenological study of sounds but
rather a study pertaining to "judgments about sounds," and
it belongs therefore to the field of psychology in the narrow sense.
(Stumpf, 1906a, p. 31) Stumpf makes it clear, however, that the
judgment in question is not categorical but it is a judgment of a
particular type which he calls apprehension or apperception. Stumpf
claims moreover that there are sensory contents which are not related
to judgments or any other mental functions such as space as he had
demonstrated in his *Raumbuch*. (see J. Bouveresse, 2006) Two
important contributions from Stumpf in this book (Kaiserl-El-Safti,
2011, pp. 38-39) rely on the famous concept of fusion
(*Verschmelzung*) by which he characterizes the phenomenon of
consonance, which in turn constitutes the foundation of music, and the
theory of relations that Stumpf develops in the first volume of this
work. (Stumpf, 1883, SS 6) This theory of fusion led to a debate
with Brentano (see C. Allesch 2003, R. Martinelli, 2013) and the
importance of this notion in Husserl's phenomenology is
well-known, particularly in relation to the latter's conception
of figural moments. (C. Ierna, 2009)



In the field of psychology, Stumpf's name is also associated
with the famous case of Clever Hans, which aroused great interest in
the early twentieth century, and which represented a significant step
in the development of experimental psychology. (H. Baranzke, 2001 W.
Prinz, 2006 H. Gundlach, 2006) We know that Stumpf's assistant,
O. Pfungst devoted an entire book to the case of Clever Hans in which
he presented the results of the investigation that he and Stumpf
conducted. (Stumpf, 1907a, pp. 7-15) Similarly, Stumpf
contributed to the foundation of the anthropoid station in Tenerife
where Kohler (1925) conducted his well-known research on
chimpanzees. Stumpf was also interested in other similar phenomena,
such as the study of child prodigies like Pepito Arriola and many
others. He founded in 1901 the Society for Child Psychology and
contributed two studies on that topic (Stumpf, 1900, 1901)


## 10. Stumpf's Legacy



The work of Carl Stumpf has aroused much interest since the turn of
the twenty-first century. Over the past fifteen years, in addition to
the publication of numerous translations and reprints of
Stumpf's writings, several articles and books have been devoted
to examining and evaluating the different aspects of his work. The
recent reception of Stumpf's work is very diversified and it
reflects the interdisciplinary nature of his research and his many
accomplishments at an academic as well as an institutional level. (G.
Frechette, 2010; M. Kaiser-El-Safti, 2011; D. Fisette
2015a)



At the very end of his autobiography, Stumpf confesses that he never
sought to establish a school and that he is grateful to those of his
students who pursued their research based on their own plans in the
same scientific spirit. Stumpf's words are confirmed by the
testimonies of many of his students who all shared this scientific
spirit and described Stumpf as a model of precision and clarity in
thought and observation, with a keen sense for analysis and a critical
attitude towards his own philosophical thought. If indeed he did not
establish a school, he is however responsible for the formation of
outstanding researchers and philosophers, and he has contributed
directly to the development of two of the most important movements in
Germany at the beginning of the twentieth century: Gestalt psychology
and phenomenology. But Stumpf also counts as one of the harshest
critics of these two movements as evidenced in his
*Erkenntnislehre*, a posthumous work in which he presents the
essential elements of his *Weltanschauung* and, in a sense, his
philosophical testament. Let us remember that this book is dedicated
to Brentano and can therefore be considered a contribution, the last
in importance in the school of Brentano, to the philosophical program
of his mentor. It is not surprising, therefore, that the criticism he
addressed to his own students in this work was mainly motivated by
this program.



In this work, he offers a remarkably penetrating analysis of the
philosophical project that guided Husserl in the first book of
*Ideas*. From Stumpf's perspective, the originality of
this new version of phenomenology in *Ideas I* lies less in the
aspects in which he criticizes the doctrine of the *Logical
Investigations* whereby phenomenology is defined as descriptive
psychology than in the features by which Husserl opens up new
perspectives with respect to descriptive psychology and phenomenology
in Stumpf's sense. This is the case of phenomenology understood
as a doctrine of essences, whose aim is to ground the empirical
sciences on the so-called regional ontologies. This endeavor belongs
to the more general project of a general theory of science which
Husserl worked out in this work. Stumpf understands this project as a
widening of Brentano's and Lotze's initial program which,
according to him, is nothing other than a regional phenomenology or
ontology in the sense of Husserl. However, he does not see any
progress in the idea of a "pure" or transcendental
phenomenology nor in the postulate of a pure ego to which something
like a "*rein Ichblick*" is purported to give
access. For if this purity is acquired on the basis of the method of
the reduction, more precisely the eidetic reduction, than by
bracketing the existence of objects, it rules out *eo ipso* any
possible contribution on the part of the empirical sciences. Stumpf
also questions the status of sense perception and the domain of
phenomena in this perspective given that Husserl's
*Wesensschau* can only be applied to what Stumpf calls mere
presentations or second-order phenomena. In his remarks on Stumpf in
Section 86 of *Ideas I*, Husserl pointed out that the study of
phenomena belongs to what he calls in the introduction to this work
"eidetic psychology." But as a science of facts and of
realities, this psychology falls under the reduction and does not seem
to contribute significantly to the version of transcendental
phenomenology put forth in *Ideas I*. Stumpf concludes that
this version of phenomenology is a phenomenology without phenomena due
both to Husserl's account of phenomena and to his peculiar
conception of (transcendental) phenomenology. (R. Rollinger, 1999,
2008c; D. Fisette, 2015b)



As we said, in 1900, Stumpf established the Institute of psychology in
Berlin which was at the origin of the original movement in psychology
called Gestalt psychology. With the exception of Max Wertheimer, who
did his dissertation in 1904 under the direction of Kulpe in
Wurzburg, the other psychologists of the Institute of Berlin,
Wolfgang Kohler, Kurt Koffka, Kurt Lewin, Egon Brunswik and
Adhemar Gelb undertook their apprenticeship in psychology and
philosophy under Stumpf's supervision. This is also the case of
Robert Musil and C. von Allesch. However, although the Gestaltists in
Berlin had initially adopted Stumpf's phenomenological
standpoint, they departed significantly from Stumpf's conception
of the mind. (M. Ash, 2000-2001, 1998; F. Toccafondi, 2009).
Despite Stumpf's significant contribution to the debate on the
nature of Gestalt and psychology in general, he was targeted by
Kohler (1913) in his classical paper on the constancy hypothesis,
and which is sometimes considered to be the very beginning of Gestalt
psychology. Stumpf replied to this objection in his posthumous book by
saying that Kohler was wrong in eliminating founding contents in
favour of the constancy hypothesis. The following excerpt from his
book *Erkenntnislehre* summarizes the main issues in this
dispute:



> 
> In the presentations of the Gestalt psychology, it is as if there were
> absolutely no sound and no color, nothing absolute in our sense
> perceptions, but only Gestalts. Gestalts alone seem to be the only
> original data while sounds, colors and everything that we call
> phenomena would only come apart by means of abstraction. (Stumpf,
> 1939, p. 242)
> 



In summary, Stumpf claims that, in this conception of Gestalt,
"the forest hides the trees." For Stumpf maintains that
the whole is prior to its parts and that each part, in virtue of its
nature, is conditioned by the whole. However, he cannot allow the idea
that one may perceive a Gestalt without presupposing a founding
content or what he also calls first-order phenomena such as, for
instance, color or sound. Stumpf's conception of Gestalt is
closer to that of Buhler (D. Fisette, 2015c) in that it consists
in a "complex of structural relations." (Stumpf, 1939, p.
246) Another quote from his posthumous work summarizes perfectly the
theoretical issues at stake in Stumpf's criticism of his
students:



> 
> The conception of the perception of Gestalts which is advocated here
> presupposes: 1. The possibility of perceiving relations; 2. The
> possibility of unnoticed content in consciousness; 3. The distinction
> between phenomena and mental functions as heterogeneous contents of
> consciousness. If one admits these three theses, then our theory is
> founded. If one challenges it, then one will be led to the native
> Gestalt psychology, but also to all the difficulties that come with
> it. (Stumpf, 1939, p. 254)
> 



According to Stumpf, the cost for adhering to the native theory is
nothing less than to abandon the very principles of descriptive
psychology and phenomenology. Moreover, besides the difficulties
mentioned by Stumpf in this passage, Gestalt psychology conveys
philosophical presuppositions which are at the heart of the dispute.
The first is a form of sensual naturalism that Stumpf rejects. The
second assumption concerns the metaphysical question of psychophysical
relations in Kohler's work and the attempt to introduce the
concept of Gestalt in the field of physics. Stumpf believes that
Kohler's isomorphism thesis, which postulates the existence
of an identity relation between the structural laws of the psychical
world and that of the physical world, presupposes the theory of
psychophysical parallelism, which Stumpf rejects as well.