## 1. Christian Thomasius


### 1.1 Life and Works



Christian Thomasius was born on 1 January 1655 in Leipzig. He was the
son of Jakob Thomasius (1622-84), a well-known jurist and
philosopher at the University of Leipzig who counted Leibniz among his
students. Christian (hereafter simply 'Thomasius')
matriculated in the philosophy faculty at Leipzig in 1669, and was
promoted to *Magister artium* in 1672. As a result of his
father's lectures, particularly on Hugo Grotius' *De
jure belli ac pacis*, and his interest in Samuel Pufendorf's
*De jure naturae et gentium*, Thomasius took up the study of
law in Frankfurt an der Oder in 1675 and was awarded a doctorate in
1679. After a brief journey to Holland, Thomasius returned to Leipzig
where he worked (unhappily) as a lawyer while also holding private
lectures on natural jurisprudence. Thomasius attests to the
fundamental reorientation of his thinking effected by his reading of
Pufendorf, and the *Apologia pro se et suo libro* (1674) in
particular, which he credits for convincing him of the independence of
natural law from theology as well as of the need to question authority
and resist religious intolerance (Thomasius 1688a, "Diss.
Proem." SSSS5-10; Hochstrasser 2000:
113-121). This new anti-authoritarian cast of mind is clearly
evident in a dissertation on bigamy of 1685, in which Thomasius
defends the practice as consistent with natural law, and which
unsurprisingly led to a confrontation with a professor in the theology
faculty at Leipzig. Thomasius' pioneering decision to hold
lectures in German, announced (in German) in 1687, likewise provoked
controversy, as did his publication beginning in 1688 of a monthly
journal (the first periodical published in German), entitled the
*Monatsgesprache*, in which Thomasius commented,
frequently satirically, on the local intellectual scene.
Thomasius' lectures and publications increasingly generated
conflict with the theological faculty in Leipzig, which upheld a
rather strict form of Lutheran orthodoxy, and while his connections
with the Saxon court stood him in good stead for a time, his defence
of an inter-faith marriage involving a (Lutheran) Saxon count and a
(Calvinist) Brandenburg princess cost him his protection, and in March
1690 he was prohibited from publishing and holding lectures (private
and academic) in Electoral Saxony.



Thomasius sought refuge in Berlin, in the neighbouring state of
Brandenburg which was led by the Calvinist Elector Friedrich III
(later king Friedrich I) and had a tradition of toleration. Partly
through the support of Pufendorf himself, Thomasius was given an
appointment as councillor to the court, and was allowed to lecture at
the Ritterakademie in Halle an der Saale, which in 1694 would become
the Friedrichs-Universitat, with Thomasius among the founding
faculty (in law). Thomasius was soon joined by the Pietist
orientalist, theologian and educational reformer, August Hermann
Francke, who had likewise run afoul of the religious authorities in
Leipzig. Thomasius himself had been sympathetic with the
anti-scholastic and anti-authoritarian bent of the Pietists (see
 SS3.2
 below), and had publicly defended Francke at one point in Leipzig;
however, a public break occurred when Thomasius published a criticism,
in 1699, of the pedagogy Francke had adopted in his famous educational
institutions in Halle. Thomasius continued to stir controversy with
his lectures and publications, which frequently over-reached the
purview of the juristic faculty (such as his critical discussion of
witchcraft trials--Beck 1969: 253-254), and breached
decorum by personally attacking his theological colleagues, all of
which led to a reprimand from the Brandenburg court in 1702 and an
order to adhere to the boundaries between faculties. Thomasius'
dissertation *De concubinatu* of 1713, in which he contended
that the use of concubines does not violate the marriage contract
given that the purpose of marriage is solely procreation, also
generated heated discussion. While Thomasius and Francke reconciled in
1714, Thomasius did not play a significant role in the later
controversy between Wolff and the Pietists. He died in Halle on 23
September 1728.



Thomasius' works cover a wide range of topics. In addition to
the topical essays and dissertations already mentioned, Thomasius
published major texts on natural law, including the *Institutiones
jurisprudentiae divinae* (*Institutions of Divine
Jurisprudence*) of 1688 and the *Fundamentum iuris naturae et
gentium* (*Foundations of the Law of Nature and Nations*)
of 1705 (for discussion of Thomasius' contributions to natural
law theory, which will not be taken up here, see especially
Hochstrasser 2000: ch. 4; Kuhnel 2001; and Lutterbeck 2002).
Thomasius also published on topics in theoretical and practical
philosophy, especially during his time in Halle. Thomasius wrote a
number of texts on logic, such as the *Introductio ad philosophiam
auliam* (*Introduction to Court Philosophy*) of 1688, as
well as the *Einleitung zur Vernunfft-Lehre* (*Introduction
to the Doctrine of Reason*) and the *Ausubung der
Vernunfft-Lehre* (*Application of the Doctrine of Reason*)
both of 1691. These were followed by a parallel exhibition of his
moral philosophy in the *Einleitung zur Sitten-Lehre*
(*Introduction to the Doctrine of Morals*) of 1692 and the
*Ausubung der Sitten-Lehre* (*Application of the
Doctrine of Morals*) of 1696, as well as an influential excursion
into metaphysics in the *Versuch von Wesen des Geistes*
(*Essay on the Essence of Spirit*) in 1699 (second edition
1709).


### 1.2 Philosophy



Thomasius is decidedly not a systematic philosopher; instead, and
quite consistent with his mature distaste for dogmatism in all its
forms, he is best characterized as a conscientiously eclectic thinker
(M. Albrecht 1994: 398-416; Bottin & Longo 2015:
301-315). That said, Thomasius' thought is unified by an
overarching conviction in the priority of practical life, and the
belief that erudition in whatever sphere of knowledge should be
pursued for the sake of the improvement of our will and intellect for
use in our ordinary life. This is made clear, for instance, in the
definition of learnedness ("*Gelahrheit*") that
Thomasius provides at the outset of his *Introduction to the
Doctrine of Reason*:



> 
> 
> Learnedness is knowledge through which the human being is made capable
> of properly distinguishing the true from the false and the good from
> the bad [...] in order that one might promote one's own
> temporal and lasting welfare, and that of others, in ordinary life and
> affairs. (Thomasius 1691a: ch. 1, SS1 [2019: 18])
> 
> 
> 



Significantly, and unlike subsequent Enlightenment thinkers, Thomasius
is also explicit in holding that because the attainment of learnedness
is possible wholly through the use of the natural (rather than the
supernatural) light of the mind (cf. Thomasius 1691a: ch. 1,
SS16), it is accessible by all, regardless of gender or class (for
more on this, see
 SS6.1,
 below).



In light of this, the aim of logic for Thomasius is to cultivate the
powers of the mind, and the faculty of reason in particular, so that
we are capable of discerning what the natural light of the mind
reveals to be true or false in any field to which it is applied. This
involves not just supplying positive guidance with respect to how
truth might be recognized and attained, but also negatively
identifying and dispelling prejudices that obscure the natural light.
Thomasius' logic, therefore, is not primarily intended to offer
a theory of demonstration (as with scholastic logics) nor an organon
for specifically scientific discovery (as with Cartesian logics or,
later, with Wolff's logic). This distinctive aim does not,
however, prevent him from weighing in on matters of traditional
logical and epistemological import; for instance, he contends that
thought has to do with images ultimately derived from the external
senses (thereby rejecting innate ideas--Thomasius 1691a: ch. 3,
SS22), and he outlines a theory of demonstration that focuses on
preserving *conviction* in truths through their connection to
incontrovertible first principles.



Thomasius' *Application of the Doctrine of Reason*
contributes to the project initiated in the *Introduction* by
outlining the means of avoiding error. Avoiding error involves the
eradication of prejudices, which are among the causes of the
corruption of reason and which are grouped into two main groups,
namely, prejudices of authority and of precipitancy or hastiness.
That, in turn, is accomplished through what he identifies as dogmatic
doubt, not the Cartesian doubt that deems everything false so as to
find a first indubitable principle, which is a pointless enterprise,
according to Thomasius. Dogmatic doubt is the doubt about particular
things, beliefs, and opinions, and this he found healthy and conducive
to preventing error.



In any case, the centrepiece of Thomasius' logic, and probably
its most influential aspect, is his theory of truth. According to
Thomasius' definition, truth consists in



> 
> 
> *nothing other than an agreement between human thoughts and the
> constitution of things outside your thoughts.* (Thomasius 1691a:
> ch. 5, SS13 [2019: 28]; italics in original)
> 
> 
> 



While this definition *contains* the classical correspondence
theory of truth (in accordance with which truth consists in the
correspondence of our thoughts with things), Thomasius contends that
the correspondence works in the other direction as well, namely, that
truth also requires the correspondence of things with our powers of
thought:



> 
> 
> Here, however, you should not ask whether the understanding must agree
> with things, or the things with the understanding; rather this harmony
> is so constituted that neither provides the guiding principle for the
> other, but this harmony is simultaneously presupposed by both even
> though external things as it were initiate it. (Thomasius 1691a: ch.
> 5, SS14 [2019: 28])
> 
> 
> 



In accordance with this conception of truth, Thomasius conceives of
the mind as fundamentally active with its ideas (rather than merely
passively reflecting the order of nature) such that things must be in
agreement with its nature and capacities in order to be cognized or
willed. Thomasius does not himself explore the principles that might
govern the mind's activity nor draw any idealistic consequences
from this conception of truth--that, for instance, things insofar
as they agree with our intellect might differ considered apart from
it--though his successors such as Adolph Friedrich Hoffmann and
Christian August Crusius would (on the latter, see
 SS5.2
 below).



This conception of the human mind as fundamentally active is taken up
again in Thomasius' lone substantial contribution to
metaphysics, the *Essay on the Essence of Spirit*, where
Thomasius distinguishes spirit (*Geist*) from matter in virtue
of its activity. While this would appear to result in a metaphysical
dualism, Thomasius complicates things by endorsing a hierarchy of
spirits, not just between the human being and God, but also a class of
spirits responsible for various effects in bodies (such as heating and
cooling). Yet, his further postulation of an "air and light
spirit [*ein Lufft- und Licht-Geist*]" which fills the
spaces between parts of matter, not to mention his apparent
identification of space itself as "pure spirit" (Thomasius
1709: 60, 167-8) muddles the original, starkly dualistic
picture.



Thomasius's moral theory is a theory of the will. He held that
in moral matters, the will dominates reason. While human beings have
free choice if not externally constrained, the will is not free;
rather, it is dominated by human affects--our passions, impulses,
and desires. Like Hobbes, Thomasius believed that even though subject
to such inner (psychological) constraints, the will still chooses
(with the aid of reason); it consciously wills. And a conscious choice
is precisely what is required for a (good) action to be considered
moral: a good instinct or good inclinations may make us good, may even
be desirable, but by itself this is not enough to make us moral.
Morality requires a conscious act of will. The trouble with morality
arises because the will is determined by evil desires, in particular,
lust, ambition, and avarice. Although there are noble sentiments as
well, which similarly influence the will, they are in conflict with
the negative dispositions. The conflict can be brought to a positive
conclusion only by appeal to divine grace (God's salvation), and
Thomasius *Application of the Doctrine of Morals* is notable
for its positive treatment of mystical experience.



Thomasius' moral philosophy is accordingly informed by
theological considerations in a way not shared by his works in
theoretical philosophy. While, in the theoretical context, he did
believe in natural reason's capacity to overcome corruption, in
the practical context he held that an evil will is at the root of our
corruption, and to ameliorate it we require God's grace.
Moreover, Thomasius's moral outlook seems to develop from his
initial presentation of morality in the *Introduction to the
Doctrine of Morals* in 1692, which is an optimistic affirmation of
the viability of a moral position he identified as one involving
"rational love" (*vernunftige Liebe*) as the
only means to a "happy, courteous and cheerful life", to a
more pessimistic position in his *Application* in 1696 where he
contends that human self-interest and an evil will constitute
significant obstacles to moral improvement (a development likely due
to his Pietist conversion during the period; cf. Beck 1969: 251;
Ahnert 2006: 27-42).



This ambivalence and return to theology aside, Thomasius's moral
position is a distinctive one. The theory of rational love is based on
the fundamental equality of human beings as well as on their ability
to think and choose independently (of authority). Ultimately,
Thomasius's ethics is a social ethics. The theory is
other-directed, and given the absence of laws and principles,
constitutes a contrast to the formalist universalist ethics Kant would
develop by the end of the next century. At the same time, the lack of
any way of making this theory applicable in a context governed not by
similar but instead by conflicting interests, makes something like a
formalist ethics an inevitability. By the end of the *Introduction
to Moral Theory*, even Thomasius recognizes that "rational
love" will function only in relatively harmonious contexts. In
other contexts, however, particularly those characterized by unequal
power positions, justice may well be required, a distinction in duties
which Thomasius influentially characterizes in terms of
"internal" and "external" obligation (cf.
Barnard 1988; Schneewind 1998: 165-166).


## 2. Radical Philosophy



Through the efforts of Thomasius, and later Christian Wolff, the
Friedrichs-Universitat in Halle became the intellectual centre of
the early Enlightenment in Germany. And despite, for instance,
Thomasius' conflict with Orthodox Lutheranism in Leipzig, and
Wolff's controversy with his Pietist colleagues
 (SS3.3,
 below), neither were explicitly hostile towards religious belief, the
Church, or to (appropriately exercised) religious authority; nor for
that matter did either seek to challenge the existing political order.
Beyond the German academy, however, a more radical philosophical
tradition flourished, one that drew on the thought of, among others,
Hobbes, Gassendi, and Spinoza, and proliferated through the
transmission of clandestine literature within networks that spanned
across Europe. While there was considerable diversity among the views
held by the thinkers within this radical philosophical tradition, they
tended to be highly critical of organized religion (if not necessarily
professed atheists) and of the established political order, rejected
the authority of the Bible as a source of revealed truth, and defended
a (not always sophisticated) materialistic conception of the soul (cf.
Stiehler 1966; Israel 2001: 628-636; Mulsow 2006 [2015]). It
bears noting that while this tradition flourished outside of a narrow
academic context, there was nonetheless considerable exchange and
mutual influence between figures in both the mainstream and radical
traditions.



Among the most important German thinkers within this radical
philosophical tradition, and quite representative of its intellectual
diversity, are Friedrich Wilhelm Stosch (1648-1704) and Theodor
Ludwig Lau (1670-1740). Stosch was the son of a Reformed
minister and court chaplain in Brandenburg and worked as a court
secretary until ill-health forced him to resign in 1686. Stosch
subsequently pursued philosophical interests and in 1692 published his
sole known text, the *Concordia rationis et fidei* (*Concord
of Reason and Faith*). In spite of its title, the *Concord*
seeks to subordinate the claims of faith to the canons of reason, in
accordance with a broadly Socinian outlook, and Stosch denies that
there is any basis in reason for conviction in the natural immortality
of the soul (for which he also provides a materialist account), and
rejects the reasonableness of eternal damnation. Stosch's
*Concord* was published anonymously (with Amsterdam listed as
the place of publication) with only 100 copies printed, but when these
were discovered for sale, they were seized and burned. Stosch was
forced to identify himself as the author, was arrested, and
subsequently investigated by a committee consisting of, among others,
Pufendorf, concluding with Stosch's public retraction of the
book in 1694.



Lau had studied law in his home town of Konigsberg before moving
to Halle in 1694 where he attended lectures by Thomasius. In 1695, he
embarked on a trip through Europe and England (where he apparently met
Newton), taking up a position as councillor with the young Duke of
Courland on his return. The early death of his patron saw Lau turn to
intellectual pursuits, and in 1717 he published a number of treatises
on various subjects, including the anonymous *Meditationes
philosophicae de Deo, mundo et homine* (*Philosophical
Meditations concerning God, the World, and the Human Being*). The
text covers a wide range of philosophical (and medical and political)
topics, and is distinctive in its eclectic borrowings from Spinoza,
Locke, Plotinus, and Giordano Bruno, among others. Its general
philosophical outlook might most accurately be characterized as
pantheistic, both in the Spinozistic sense inasmuch as Lau defends the
world's pre-existence in God and denies its creation *ex
nihilo* (although the extent of Lau's Spinozism is disputed;
cf. Schroder 1987: 128-132), but also and especially in the
sense of the Irish freethinker John Toland's pantheism inasmuch
as Lau attempts to outline the foundations of a universal religion.
Due to its strident denunciation of the clergy and a genealogical
critique of the current political order, the *Meditations* was
instantly controversial, and Lau's publisher was eventually
pressured into revealing Lau's authorship. This led to
Lau's imprisonment, during which he attempted suicide, and his
subsequent expulsion from Frankfurt am Main; Lau's appeal to his
mentor, Thomasius, for a review of the proceedings was also met with a
painful denunciation. Lau attempted to return to his study of the law,
but his unorthodox opinions and previous brush with infamy made this
impossible (in spite of a formal recantation of his earlier views). He
died, in poor mental health, in Altona in 1740.


## 3. The Controversy between Wolff and the Pietists



Thomasius would continue to exercise an important influence on German
philosophy throughout the first half of the eighteenth century.
However, it was his colleague in the philosophy faculty at the
Friedrichs-Universitat, Christian Wolff, who would contribute the
most to the modernization of the German intellectual landscape and the
spread of the Enlightenment. Wolff achieved this primarily through his
distinctive philosophical system, the so-called
"Leibnizian-Wolffian" philosophy, which incorporated the
latest philosophical ideas and methods, including but not limited to
those of Leibniz himself. The relevance and accessibility of
Wolff's system, expanded and refined by his many students,
quickly saw it gain a foothold in academies across Germany. Wolff was
not without his detractors, of course, and none were more vocal, nor
more successful (at least initially) in their efforts to limit his
influence, than his Pietist colleagues in the faculty of theology. The
famous controversy between Wolff and the Pietists, which at its climax
saw Wolff exiled from Prussia on pain of hanging in 1723, put the full
menu of modern ideas--including materialism, idealism, atheism,
and Spinozism--before the literate public and drew the attention
of the rest of Europe to the German intellectual scene.


### 3.1 The "Leibnizian-Wolffian" Philosophy



Christian Wolff was born in Breslau (today, Wroclaw) on 24
January 1679. By all accounts a gifted student, he developed an
interest in theology and mathematics during his time in Gymnasium, and
studied theology and mathematics at the University of Jena and then in
Leipzig, gaining his *Magister* at Leizpig in 1702. His
subsequent *Habilitationsschrift* on introducing mathematical
method to practical philosophy drew Leibniz's attention to him.
They began a correspondence that continued until Leibniz's death
in 1716, and which covered topics from mathematics to metaphysics.
Partially through Leibniz's support, Wolff was appointed to a
vacant chair in mathematics at the Friedrichs-Universitat in
Halle, delivering his inaugural lecture in 1707.



Understandably, given the nature of his position, most of
Wolff's initial publications were devoted to mathematics and
natural science, including an introduction to mathematics in 1710 and
an influential mathematical dictionary in 1716. Around 1710, however,
he began to lecture on more narrowly philosophical topics, publishing
his *Vernunfftige Gedancken von den Krafften des
menschlichen Verstandes und ihrem richtigen Gebrauche in
Erkantnis der Wahrheit* (*Rational Thoughts on the Powers
of the Human Understanding and its Propert Use in the Cognition of
Truth*) [the "*German Logic", hereafter GL*] in
1713. Thus began Wolff's famous series of German-language
textbooks on philosophical topics, which would grow to include the
*Vernunftige Gedanken von Gott, der Welt und der Seele des
Menschen, auch allen Dingen uberhaupt* (*Rational Thoughts
on God, the World and the Soul of Man, and on All Things in
General*) [the "*German Metaphysics*",
hereafter GM] in 1719 (albeit with a publication date of 1720), and
the *Vernunfftige Gedancken von der Menschen Thun und Lassen,
zu Beforderung ihrer Gluckseligkeit* (*Rational
Thoughts on Human Actions for the Promotion of their Happiness*)
[the "*German Ethics*", hereafter GE] in 1720,
followed by the "*German Politics*" in 1721, the
"*German Physics*" in 1723, and the
"*German Teleology*" in 1724.



This series of texts constitutes the first presentation of the
so-called "Leibnizian-Wolffian" philosophy that would come
to dominate the philosophical landscape in Germany. There is, of
course, no question that Wolff's philosophical system is
thoroughly informed by Leibniz's: Wolff himself admits that the
reading of Leibniz's 1684 essay "Meditations on Cognition,
Truth, and Ideas", and Leibniz's classification of ideas
in particular, had sparked a "great light" that informed
his *German Logic* (cf. GL "Vorrede"); moreover,
Wolff himself reports that he incorporated a number of Leibnizian
concepts into his presentation of ontology, cosmology, and rational
psychology in the *German Metaphysics* (cf. Wuttke 1841:
141-142). Even so, Wolff points out that when he started writing
his series of philosophical textbooks there were few of
Leibniz's texts available through which one might get a sense of
the wider Leibnizian philosophy (Wuttke 1841: 140-141; cf. also
Wilson 1994); thus he takes issue with the designation of his system
as "Leibnizian-Wolffian"--a coinage he credits to one
of his students, Georg Bernhard Bilfinger (Wuttke 1841: 142). The
extent of Leibniz's influence on Wolff is widely debated (cf.
Corr 1975; Ecole 1979), but it is in any case clear that
Leibniz is not the sole, nor in every case the most important,
influence on the development of Wolff's ideas, as figures such
as Ehrenfried Walther von Tschirnhaus (1651-1708), John Locke,
and late Scholastic thinkers also exerted an important influence on
his metaphysics, epistemology, and theory of science (Neveu 2018;
Leduc 2018; Dyck 2021a).



Turning to a brief overview of Wolff's philosophical works, the
*German Logic* is intended, quite in contrast to
Thomasius', as a handbook for the acquisition, justification,
and orderly presentation of scientific cognition. So, in addition to
the now expected treatment of concepts, propositions, and syllogisms,
Wolff's text contains discussion of drawing universal
propositions from individual experiences, of experiments, and of
science and its distinction from faith and opinion. Moreover, the
*German Logic* contains Wolff's mature presentation of
his mathematical method, through which we proceed from definitions and
axioms to the formulation of theorems and postulates, and ultimately
to demonstrations, and it outlines how the method can be employed for
the purpose of scientific discovery (for discussion, see Frketich
2019; Gava 2019). Significantly, it is this method that gains
widespread application throughout Wolff's philosophical
enterprise, including in his metaphysics.



The *German Metaphysics* was Wolff's next major
philosophical text, and in it he formally introduces the division of
metaphysical topics into ontology, cosmology, empirical and rational
psychology and natural theology, a division that Kant, among others,
would subsequently take up. The initial chapter attempts to make
evident, in a Cartesian vein, both an indubitable truth ("we are
certain that we exist") and to establish a canon for what will
count as a *certain* cognition for the remainder of the
enterprise. In the second chapter Wolff sets out the two (Leibnizian)
principles governing his philosophical thought: the principle of
contradiction ("something cannot both be and not be at the same
time" GM SS10) and the principle of sufficient reason.
Significantly, Wolff suggests that while the first is self-evident,
the second admits of proof, for which Wolff (in a departure from
Leibniz) offers two arguments. The first proceeds as follows:



> 
> 
> Were it the case that something could be, or take place, in a thing
> without a reason why it should occur being met with either in that
> thing itself or something else, then it would come to be from nothing.
> Since, however, it is impossible that something could come to be from
> nothing, *everything that is must have a sufficient reason why it
> is*. (GM SS30 [2019: 101])
> 
> 
> 



In the remainder of the ontology, Wolff provides accounts of concepts
that will be key for his subsequent treatment of specific metaphysical
topics, including essence and attribute, space and time, simple and
composite, substance, power, and cause.



The chapters on empirical and rational psychology outline an account
of the soul in general and of the human soul in particular. In his
empirical treatment, Wolff considers what can be known of the soul by
means of our ordinary inner experience. He contends that we can
distinguish thoughts in terms of obscurity, clarity, and distinctness,
but we can also distinguish the soul's representations in terms
of their content. Accordingly, they can be classified into sensations,
imaginings, and thoughts proper, which can in turn be traced back to
various faculties of the soul, including sensibility, imagination, and
the understanding, in virtue of which it is capable of these distinct
thoughts. We also discern that the soul is subject to pleasure and
displeasure in its (distinct or indistinct) cognition of good and
evil, which give rise to desires and willing (based on indistinct and
distinct cognition respectively), and when that willing is in
accordance with what pleases the soul the most then, for Wolff, its
acts are free (GM SS519).



On the basis of these empirical cognitions of the soul, rational
psychology seeks to draw inferences regarding the soul's essence
and nature. Wolff argues that the soul must be immaterial given that
it is impossible that a body should think (GM SS738), and as a
result that the soul is a simple substance endowed with a power of
which its thoughts are effects, which power is identified as a power
of representation (GM SSSS742-7). This secures the
soul's natural immortality, or incorruptibility, but Wolff
argues for the soul's personal immortality, or its preservation
of its state of conscious representation and memory in the afterlife
(GM SSSS925-6). It is in the context of rational
psychology that Wolff also offers a defence of the Leibnizian doctrine
of pre-established harmony (SS765), which he think accounts for
the empirically-observed agreement between the states of the soul and
the body better than the competing systems of physical influence and
occasional causation.



The final pair of topics concern the world (cosmology) and God
(natural theology). Regarding the former, Wolff identifies the world
as the "series of changeable things that are next to one another
and follow one upon the other" (GM SS544 [2019: 120]). As
such, the world is a composite consisting of ultimately simple
substances, though Wolff declines to identify them as Leibnizian
monads as he hesitates to ascribe representational states to the
constituents ("elements") of matter (GM
SSSS598-9). Things and events in the world are
nonetheless connected to one another in accordance with the principle
of sufficient reason, and Wolff concludes that all events are certain
as a result (GM SS561). Concerning God, Wolff argues that He must
exist inasmuch as our own evident existence requires a necessary being
to serve as its sufficient reason, which necessary being must also be
independent, eternal, and simple (GM SSSS928-936); it
cannot, therefore, be the world (a composite) nor our own soul (a
being dependant on the world), and so can only be God (GM SS945).
In addition to these attributes, God must have an understanding,
through which He distinctly represents all that is possible, and a
free will inasmuch as He chooses that world which pleases Him most to
make actual (GM SS980).



Rounding out Wolff's major philosophical works of this period,
the *German Ethics* is composed of four parts, a theoretical
part that treats the foundation of practical philosophy and three
practical parts that present a doctrine of duties that human beings
have towards themselves, God, and others. The central notion in
Wolff's ethics is the (metaphysical) notion of perfection which
concerns the "agreement" of elements in a given manifold
(cf. GM SS152), and which is cognized through our intellectual
powers. It is the cognition of the (apparent) perfection in an action
that moves us to act, a fact that accounts for Wolff's emphasis
on the duty to cultivate our understanding among our duties to
ourselves so that we can be moved to act in (what are in fact) the
most perfect ways. Promoting the perfection of ourselves and others
serves for Wolff as the universal rule in accordance with which we
ought to choose between two (or more) possible actions (GE SS12).
That is to say, when making a free choice we ought to consider whether
the action "promotes the perfection of our inner and outer
state" (GE SS2) and that means considering whether the state
of the soul and the body accords with the prior state or contradicts
it. The outcome has greater perfection to the extent that it
contributes to the continued "natural human state and its
harmonious preservation over time"(GE SS2). The natural
human state Wolff envisions is the state of the soul in its manifold
efforts to find truth, and everything has to be done to maximize that
state. It so happens, that this is where happiness lies as well, and
as Wolff indicates at the end of the ethics, it is incumbent upon
human beings to ensure not only their own perfection/happiness, but to
"contribute as much as possible to the happiness of
others" (GE SS767).


### 3.2 The Halle Pietists



Next to Thomasius and Wolff, the most important intellectual figure in
the early history of the Friedrichs-Universitat in Halle was
August Hermann Francke (1663-1723). As we have seen, Francke had
courted controversy in Leipzig through his involvement in the Pietist
movement. Pietism was a spiritual movement within the Lutheran
tradition that rejected the scholastic and theological turn that
Lutheranism had taken and proposed a further, internal reformation to
supplement the already-effected external one, and aimed at cultivating
a "living faith" rather than mere lip-service to Christian
ideals. The Pietists sought the personal and interior experience of a
relationship to Christ, an individual transformation that was the
result of an act of divine grace modelled on Francke's own
conversion experience (cf. Wallmann 1990: 63-4). To this end,
the Pietists focused on the study of the Bible itself and devotional
literature in small groups--the so-called conventicles or
*collegia pietatis*--which were notable, and
controversial, for welcoming the involvement of women (R. Albrecht
2004; Gierl 2015).



After falling out (in spite of Thomasius' support) with the
Lutheran authorities in Leipzig, Francke followed Thomasius to Halle.
He took up a position as a pastor in the neighbouring town of Glaucha,
and held lectures on oriental languages in 1692. Francke was himself a
disciple of the movement's intellectual founder, Philipp Jakob
Spener (1635-1705), though Francke contributed immeasurably to
the spread of Pietism, primarily through his educational institutions
in Halle, beginning with a school for poor children founded in 1695.
Through the institutions that arose from this humble school, Francke
sought a reform of educational principles in line with Pietist ideals,
and in this was enormously successful. The pedagogical institutions
supplied an influential model for similar institutions in and outside
of Germany (especially due to the fact that it was a largely
self-funded philanthropic institution), became the hub of an expansive
missionary network, and trained the next generation of German
theologians, as well as some philosophers (like A. G. Baumgarten), not
to mention Prussian civil administrators, bureaucrats, and pastors.
Indeed, Francke enjoyed a close relationship to the Prussian court,
and king Friedrich I's successor, Friedrich Wilhelm I became an
enthusiastic supporter of his projects after a visit to Halle (cf.
Hinrichs 1971).



Another significant member of the theology faculty in Halle was
Joachim Lange (1670-1744). Lange had come under Francke's
tutelage in Leipzig (where he also met Thomasius), following him to
Erfurt and (briefly) Halle, before taking up positions at various
Gymnasia in and around Berlin. During this time he also lectured on
classical languages and wrote a very successful Latin grammar. In
1709, he accepted an appointment at the Friedrichs-Universitat,
in the theology faculty that was now thoroughly steeped in
Francke's Pietism. During his time in Berlin, Lange completed a
notable philosophical work, the *Medicina mentis* (*Medicine
of the Mind*), printed in Halle in 1704. Lange's text shares
a title with Tschirnhaus' *Medicina mentis* of 1687, but
little else as Lange instead emphasizes the futility and vanity of
human attempts to attain cognition through their own efforts,
highlighting the mind's proneness to error and prejudice in its
fallen state. Rather, according to Lange, it is only by means of
divine grace and the divine light that we can heal the corrupted
intellect and the will (Schonfeld 2010).



A final figure worthy of mention in this context, albeit not
strictly-speaking a Pietist thinker, is Johann Franz Budde
(1667-1729). Budde had studied theology in Wittenberg, and after
lecturing at Jena, had been called to an appointment in moral
philosophy at Halle in 1693, where he remained until returning to Jena
in 1705 as a professor of theology. Budde adopted a conscientiously
eclectic philosophical outlook, one influenced by Thomasius, and which
also informed his theological commitments to Lutheranism (if not to
Pietism specifically). A prolific writer, he published a number of
philosophical works during his time in Halle, including the
*Institutiones philosophiae eclecticae* that appeared in two
parts in 1703. The two parts are the "Elementa philosophiae
theoreticae", roughly a metaphysics, and the "Elementa
philosophiae instrumentalis", Budde's logic. A later work,
entitled *Theses theologicae de atheismo et superstitione*
(1717), is also notable in that Budde seeks to refute various threats
to natural and revealed religion, including Spinozism (cf. Rumore
2019: 44-8), an issue that would come to the fore in the coming
controversy with Wolff.


### 3.3 The Controversy and its Aftermath



The controversy between Wolff and his Pietist colleagues is not
typically held to be of much philosophical significance. Rather, the
Pietists' hostility towards Wolff is taken to be a reflection of
their fundamentally un-enlightened anti-intellectualism, and the
outbreak of the controversy itself a result of personal and
professional rivalries--competition for students and university
chairs. That this appraisal is generally accepted is to no small
extent due to the efforts of subsequent histories of the dispute
written by devoted Wolffians, such as C. G. Ludovici (1707-78)
and Georg Volckmar Hartmann (fl. 1729-1737). And while it cannot
be denied that the voluminous texts exchanged during the course of the
controversy, on both sides, only infrequently rise above the level of
the polemical, it would be unfair to dismiss the ground of the
Pietists' objections as philosophically insignificant, or indeed
irrelevant for the subsequent development of German philosophy (up to
and including Kant).



The controversy itself was the result of long-simmering tensions
between Wolff and the Pietists. Wolff's turn to lecturing on
philosophical topics, such as metaphysics (including a treatment of
natural theology), beginning in 1710, not to mention his discussion in
the *German Logic* of Scriptural interpretation, provoked the
ire of the theology faculty and led to warnings to their students
about attending Wolff's lectures (on account of his
"*Atheisterey*"; cf. Beutel 2007: 165-6). The
publication of Wolff's *German Metaphysics* in 1719, with
its peculiar proof of God's existence and apparent endorsement
of natural necessitation, provided a broad target for their critical
attention. This largely behind-the-scenes friction broke into the open
with Wolff's address on 12 July 1721, on the occasion of the
transition of the pro-rectorship from himself to Lange, in which he
defended the consistency of Confucian (i.e., non-Christian) practical
philosophy with Enlightened reason (and Wolffian moral philosophy in
particular; cf. M. Albrecht 1985).



The address caused an uproar among the Pietists and Francke demanded
to see a copy of Wolff's address to scrutinize for himself,
which request Wolff denied citing the independence of the philosophy
faculty. Lange at this point took up the study of Wolff's
metaphysics, penning a damning appraisal for the theology faculty that
was sent to the authorities in Berlin. Wolff was invited to reply, and
his rejection of the hostile characterization of his views led to the
formation of an official commission in late October 1723 to
investigate the charges against Wolff. The king himself would soon
intervene, and decisively: after the dangers of Wolffian philosophy
were explained to two of his generals visiting Halle--the
doctrine of the pre-established harmony in particular was said to
justify the desertion of soldiers (Beutel 2001: 189)--and this
threat conveyed to the king, Friedrich Wilhelm I asked his trusted
advisor Francke to outline the problematic doctrines defended by
Wolff, which he promptly did. Horrified by Wolff's evident
godlessness, the king dismissed Wolff from his position and ordered
him to leave Prussia in 48 hours on pain of hanging, an order that was
received in Halle on 12 November 1723. Wolff reacted swiftly, crossing
over to nearby Electoral Saxony, refunding his students' fees,
and ultimately took up the offer of a position in Marburg where he
received an enthusiastic reception.



Wolff's expulsion only meant that the dispute moved into the
public domain, and the next decade would see dozens of treatises
exchanged between Wolff (and his defenders) and his opponents, Lange
and Budde foremost among them. A range of issues were canvassed in the
debate. So, the issue of the *libertas philosophandi* had
already surfaced in the conflict between the philosophical and
theological faculties, and there were significant differences between
Wolff and the Pietists concerning the ground of moral obligation
(Grote 2017); however, the principal topics were metaphysical. These
include the pre-established harmony, which Lange rejected as
inconsistent with any proper union between soul and body, defending
instead a natural connection between them achieved through physical
influx (Lange 1724: 48-50 [2019: 141-2]).



Even so, the Pietists' foremost philosophical concern was with
preserving the genuine freedom of the human (and divine) will against
Wolff's Leibniz-inspired assaults (cf. Bianco 1989). According
to Lange, Wolff's endorsement of the principle of sufficient
reason has the consequence of reducing the soul to an automaton and
rendering the series of events that constitute the world a fatally
determined concatenation. The result is a necessitarianism
distinguishable from total Spinozism only because Wolff accepts a
plurality of substances (Lange 1724: 72-3 [2019: 153]). Against
this, Lange contends that the freedom (rather than mere spontaneity)
of the will is directly evident through experience (particularly
through our conscience) and constitutes the essence of the human
being, that it is required for morality and religion, and that it
serves to exempt human beings from the chain of natural necessitation.
In spite of his unsympathetic reception in the history of philosophy,
Lange succeeds in outlining a coherent antithesis to the
Leibnizian-Wolffian conception of the soul and its place in nature,
one that would prove influential for later Pietist critics (like
Crusius) and that would also form an important part of the background
to Kant's own later discussion of freedom.



After their initial success with Wolff's expulsion, Lange and
the Pietists suffered diminished influence at the Prussian court. By
contrast, the affair only served to burnish Wolff's European
reputation. In Prussia, Wolff's works on metaphysics and
practical philosophy were added to the list of atheist books, but he
now saw himself as speaking to Europeans, not merely Germans, and
began a series of Latin works, commencing with the *Philosophia
rationalis sive logica* (*Latin Logic*) in 1728. Friedrich
Wilhelm I seemed to think better of his precipitous decision and
invited Wolff to return to Prussia in 1733, an invitation which Wolff
declined. But the ban on his writings was reversed in 1734, and the
verdict of an inter-confessional Prussian commission in 1737
vindicated Wolff's philosophy of the charges levelled by the
Pietists. The crown prince (later Friedrich II) was an enthusiastic
booster of Wolff at the court (and no friend of the Pietists), and
with his ascension in 1740 he invited Wolff to return to Prussia.
After turning down the proffered presidency of the Berlin Academy,
Wolff returned to a professor- and vice-chancellorship in Halle to
great acclaim, devoting his remaining time to completing his works on
practical philosophy.


## 4. Alexander Gottlieb Baumgarten



A. G. Baumgarten is best known for authoring the textbook in
metaphysics that Kant used for his lectures on the topic, though he
was an important and innovative thinker in his own right. His
philosophical ambitions are, moreover, deeply informed by the
controversy in Halle, as he had an abiding intellectual sympathy with
Wolffianism but theological and personal connections to the Pietists.
Among his students was the notable Wolffian philosopher Georg
Friedrich Meier (1717-77), and his own influence extended to
Kant but also to Moses Mendelssohn and J. G. Herder.


### 4.1 Life and Works



Alexander Gottlieb Baumgarten was born in Berlin on 17 June 1714.
Baumgarten's mother died when he was three, and his father, a
garrison chaplain and pastor, died when he was eight in 1722, leaving
him to the care of his grandmother and older brothers. In accordance
with his father's wishes, Baumgarten went to Halle to study,
enrolling in the Latin school at Francke's *Waisenhaus*
where his older brother Siegmund Jakob (1706-57), who would
himself become a famous theologian, was an inspector. Baumgarten
thrived in his studies, and in 1730 matriculated at the university,
where he attended lectures by Francke and Lange in theology. While it
was still forbidden to teach Wolff's philosophy, Baumgarten
undertook (with his brother's encouragement) a thorough study of
Wolff's thought, lecturing on his logic in the Latin school and
visiting Wolffians at the university in Jena. Baumgarten turned to the
study of philosophy, attaining his *Magister* in 1735, and held
lectures on logic and Wolffian metaphysics, dictating from his own
notes on the latter (rather than a textbook) from which notes his own
later *Metaphysica* derives. In 1736, a chronic lung ailment
interrupted his academic work and saw him hospitalized in Berlin,
returning to Halle in 1737 where he continued to lecture to great
acclaim. His position at Halle had been as an (unpaid) extraordinary
professor, but in 1739 he was called to a position at the university
at Frankfurt an der Oder, and he left Halle in 1740 just before
Wolff's triumphant return. In Frankfurt, Baumgarten lectured
widely in philosophy, including on aesthetics for the first time in
1742. Health problems, likely tuberculosis, and other difficulties,
marked the last decade of Baumgarten's life, and he died on 26
May 1762.



Baumgarten's philosophical works cover a wide range of topics.
The 1000 sections of his *Metaphysica* of 1739 offers a
synopsis of his views, following the Wolffian division, on ontology,
cosmology, empirical and rational psychology, and natural theology. He
also published two influential textbooks on ethics: the *Ethica
philosophica* (*Philosophical Ethics*) of 1740 and
*Initia philosophiae practicae primae* (*Elements of First
Practical Philosophy*), both of which Kant also regularly used in
his lectures on moral philosophy. Baumgarten's abiding interest
in aesthetics issued in two texts, the first a dissertation entitled
*Meditationes philosophicae de nonnullis ad poema
pertinentibus* (*Reflections on Poetry*) in 1735, and the
second the ambitious *Aesthetica*, the first volume of which
appeared in 1750, with a second unfinished volume printed (at the
request of the publisher) in 1758.


### 4.2 Philosophy



Baumgarten's metaphysics is frequently characterized as
inclining more towards Leibniz than to the
"Leibnizian-Wolffian" philosophy; for instance, he makes
explicit reference to monads in his presentation of ontology and
cosmology, and concerning the pre-established harmony he accepts that
it obtains between all substances (not just between soul and body) and
does not qualify his endorsement of the system as Wolff came to do
(Baumgarten 1739: SS761-9; cf. Watkins 2005: 73-81 for
discussion). While there is no doubt that Baumgarten adopts a
fundamentally Leibnizian picture in his ontology, including the
endorsement of the principle of sufficient reason, to leave it at this
would be to ignore the important and fruitful role that his Pietist
background plays in his philosophical thought (Look 2018). Indeed,
Baumgarten's originality as a thinker consists in his efforts to
amend key planks of Leibnizian (and Wolffian) thinking in light of his
underlying Pietist commitments.



This is particularly evident in Baumgarten's treatment of
freedom and immortality, where Wolff's position on each was
targeted by his Pietist critics. By way of addressing the Pietist
objections to Wolff's moral intellectualism and his reduction of
freedom to mere spontaneity, Baumgarten offers an enriched empirical
psychology, one that considers the influence of expectations of the
future (and a future life) as motives, that allows that immoral action
can proceed not only from ignorance but also from less lively
cognition of the good, and that explicitly distinguishes spontaneity
from freedom proper (Schwaiger 2011: 82-92). On the topic of
immortality, the Pietists had likewise objected to Wolff's
emphasis on the human soul's preservation of its
*cognitive* capacities in the afterlife, which state seems for
Wolff to be disconnected to the human's cultivation of virtue
and piety in this life. Baumgarten seeks to rectify this by arguing
that in addition to preserving its cognitive capacities in the
afterlife, the soul will also retain its moral capacities including
freedom, and that its condition of blessedness or damnation in the
life to come will be a direct function of its moral condition (1739:
SSSS782, 791; Dyck 2018).



Consistent with his orientation in metaphysics, Baumgarten is an
original moral philosopher within the Wolffian tradition. He is
notable, for instance, for the centrality of the notion of obligation
in his ethics. Wolff had framed a novel concept of obligation, rooted
in the nature of things and actions themselves rather than the will of
a sovereign, in accordance with which an obligation arises simply
insofar as some motive is naturally connected to an action (GE
SS9). Yet, whereas Wolff only treats obligation briefly before
considering specific duties, in Baumgarten's hands the problem
of obligation becomes the unifying theme for ethics, particularly in
his *Initia* (Schwaiger 2009). Moreover, while Baumgarten
accepts Wolff's ethical perfectionism, in contrast with Wolff he
downplays the connection between perfection and happiness, perhaps in
response to Pietist denunciations of Wolff's perfectionism as a
veiled form of hedonism (Schwaiger 2011: 163ff; Bacin 2015). A last
innovation is Baumgarten's consideration of the ways in which
ethical systems themselves can be flawed in that, for instance, they
make a virtuous condition too easily attainable (flattering ethics) or
set the bar for virtue too high for human nature (chimerical ethics)
(Thorndike 2008; Dyck 2012).



Turning finally to Baumgarten's aesthetics, it is notable that
while Wolff himself had comparatively little to say about the
philosophy of art (but see Beiser 2009; and Buchenau 2013), a number
of thinkers in the Wolffian interest took a keen interest in the
topic. The first to develop a theory of the arts, particularly poetry,
was Johann Christoph Gottsched (1700-1766), who published his
*Versuch einer critischen Dichtkunst vor die Deutschen*
(*Attempt at a Critical Poetry for the Germans*) in 1730.
Treating poetry scientifically, he set out a set of rules that were to
guide the composition. Given his conception of what a poem was (a
moral fable) and given as well his idea of what was involved in its
composition (a set of rules), there was little room here for beauty
and even less for sentiment and inspiration.



It was left to Baumgarten to formulate a recognizably modern aesthetic
doctrine on Wolffian foundations. This he did through focusing on the
soul's faculty of sensibility, ultimately identifying aesthetics
as the science of sensible cognition. Where Wolff had conceived of the
senses merely as providing the raw material for thinking, Baumgarten
thought that the senses had their own rules and their own perfection,
rules and perfection that differ from logical rules and the knowledge
generated by the process of intellectual clarification. So, while
representations might be logically perfect and attain to intensive
clarity insofar as we distinguish a number of marks within it,
representations of the senses, even as confused representations, can
attain to *extensive* clarity inasmuch as they represent a
multitude of things (Baumgarten 1735: SS17). In this way, poetic
representation can be richer, and more moving, than representations
attained through the use of the understanding--moving since
Baumgarten contends that such representations as (aesthetically)
perfect can also occasion pleasure in us. One cannot but see the
influence that Baumgarten likely had on Kant's Critical
philosophy -- his vindication of the senses reappears in an
inherently Kantian way both in the Transcendental Aesthetic of the
*Critique of Pure Reason* and in the *Critique of the Power
of Judgment*.


## 5. Christian August Crusius



As Baumgarten sought in a conciliatory spirit to make the Wolffian
philosophy responsive to Pietist concerns, Christian August Crusius
mounted a renewed, Pietist-inspired but philosophically-sophisticated
assault on the foundations of that system. Through his dissertations
and textbooks, Crusius succeeded in raising trenchant objections to
the Leibnizian-Wolffian philosophy, and indeed to the strongest forms
of philosophical rationalism, and he formulated an influential and
systematic alternative in which the will and its freedom are central
concerns.


### 5.1 Life and Works



Christian August Crusius was born 10 June 1715 in Leuna, near Halle,
the son of a pastor (and his mother was a pastor's daughter). He
matriculated at the University of Leipzig in 1734, where he studied a
number of subjects but was particularly interested in theology and
philosophy. At Leipzig, Crusius came under the influence of the
philosopher (and physician) Adolf Friedrich Hoffmann
(1707-1741), a disciple of Andreas Rudiger
(1673-1731) who had been a close associate of Thomasius. Crusius
attained the *Magister* in philosophy in 1737 and habilitated
in philosophy in 1740. He followed his philosophical studies with a
baccalaureat in theology in 1742, though he would proceed to seek a
position in the philosophy faculty. To this end, he defended two
dissertations in philosophy, one of which, the *Dissertatio
philosophica de usu et limitibus principii rationis determinantis,
vulgo sufficientis* (*Philosophical Dissertation on the Use and
Limits of the Principle of Determining Reason, commonly called
Sufficient*) of 1743 was a critical discussion of the principle of
sufficient reason. He became a professor of philosophy
(*extraordinarius*) at Leipzig in 1744.



Crusius' major philosophical works followed in quick succession.
He published his textbook on ethics, the *Anweisung vernunftig
zu Leben* (*Guide to Rational Living*) in 1744; this was
followed by the elaboration of his metaphysics, *Entwurf der
nothwendigen Vernunft-Wahrheiten* (*Sketch of the Necessary
Truths of Reason*) in 1745; and a text in logic, the *Weg zur
Gewissheit und Zuverlassigkeit der menschlichen
Erkenntiss* (*Path to the Certainty and Reliability of
Human Cognition*) was published in 1747 (a final philosophical
treatise on physics followed in 1749). As an ordinary professorship in
philosophy was not available, Crusius joined the theology faculty at
Leipzig in 1750. While he remained a member of the philosophy faculty
and continued his lectures (and revised his previous publications for
later editions), from this point on his original publications are
devoted to theological topics. He died in Leipzig on 18 October
1775.


### 5.2 Philosophy



Widely and rightly regarded as the most sophisticated philosopher
within the Thomasian-Pietist tradition, Crusius sets out to offer an
alternative to the core claims of the Leibnizian-Wolffian philosophy
on topics in metaphysics, epistemology, logic and practical
philosophy. As Lange had previously, Crusius targets the principle of
sufficient reason, and its employment in Leibnizian-Wolffian
metaphysics, for criticism. Crusius diagnoses a number of ambiguities
in the Wolffian presentation of the principle. He opts to refer to a
reason (*ratio*; *Grund*) that, when present, determines
something to come to be such that the opposite would be impossible as
a *determining reason*, and accordingly refers to the principle
(in the sense intended by Leibniz and Wolff) as the *principle of
determining reason* (Crusius 1743: SSII-III). Crusius
then critically discusses each of Wolff's attempts to prove the
principle--concerning the first such proof (presented in
 SS3.1,
 above), Crusius claims that the most charitable reconstruction of it
is circular. To show this, Crusius reformulates Wolff's proof as
the following syllogism (using Wolff's preferred
terminology):



> 
> 
> Whatever cannot come to be except from some other cause, has a
> sufficient reason.
> 
> 
> 
> Everything that is cannot come to be except from another cause.
> 
> 
> 
> Therefore, whatever is has a sufficient reason. (Crusius 1743:
> SSXI [2019: 207])
> 
> 
> 



As Crusius notes, however, the minor in this case is just a version of
the principle of sufficient reason itself, so that as a proof of that
principle this argument begs the question.



More positively, Crusius endorses the principle of determining reason
but denies that it admits of unlimited use, which he claims, echoing
Lange, would entail fatalism. Rather, Crusius excludes what he terms
"free first [or *fundamental*] actions" from the
scope of the principle. These actions are such that they proceed
directly from the basic powers of the acting substance under
appropriate circumstances (Crusius 1745: SS82), but are such that
they can be undertaken or omitted by the acting subject (that is, they
are not *determined*) (Crusius 1743: SSXXV). That such
actions are possible, Crusius claims, is clear given that God's
action would be of this sort, but also given the testimony of our own
inner experience, which discloses the acts of our own will to be just
such actions (Crusius 1743: SSIX). Crusius thus accepts that the
principle of determining reason holds for all events that are
*not* the result of a free first action, whereas free first
actions no doubt have a cause but are not such that could not have
occurred otherwise (or not at all).



Along with his efforts to secure a place for genuine freedom of the
will in his metaphysics, Crusius also emphasizes the limits of the
human understanding. Crusius claims that the acts of the understanding
are governed by principles, including a formal principle (the
principle of contradiction), but also and importantly a number of
"material" principles that govern what is thinkable for
the human mind (where what is unthinkable is not for that reason
contradictory). Among these principles are the *principle of
inseparability*, according to which that which cannot be separated
in thought cannot be separated in fact, and the *priniciple of
incombinability*, according to which that which cannot be combined
in thought cannot in fact be combined (Crusius 1743: SSXXVII;
1745: SS15). Significantly, and drawing on Thomasius (via Hoffmann
1737), Crusius contends that these principles which together
constitute the "essence of the understanding" supply us
with a criterion of truth, which consists in the agreement of thoughts
with things, such that only that can be true which conforms to the
principles of human understanding (Crusius 1745: SS15; 1747:
SS51). These material principles are subsequently used by Crusius
to vindicate a variety of substantive metaphysical claims, including
one he dubs the principle of sufficient *cause* (Crusius 1745:
SS31). On this basis, Crusius erects his own distinctive
metaphysics, proceeding through the now-established Wolffian topics,
though Crusius assigns natural theology a place more befitting its
importance and ignores empirical psychology because it takes up
spontaneous and free acts of the mind and so does not concern
*necessary* truths of reason, the only proper subject of
metaphysics.



Crusius' attack on Wolffianism continues in his logic and his
thoughts on moral philosophy. In a clear rebuke of Wolff, Crusius
begins his logic by rigidly distinguishing between the methods of
mathematics and philosophy, contending that where the former makes use
of demonstrations that rely solely on the principle of contradiction
(and relate to mere possibilities or hypothetical realities), the
latter must take into account other principles when, for instance, the
investigation of causes are at issue (Crusius 1747: SS10).
Commensurate with this, Crusius' considerations of the
traditional topics of logic--concepts, propositions, and
inferences--is thoroughly informed by his account of the essence
of the understanding: a philosophical inference, as opposed to a
mathematical syllogism, can have as its basis what permits of being
separated or combined in thought (Crusius 1747: SS262). Crusius
also considers the relation between philosophy and theology or
revealed religion, contending for the utility of philosophy for
students of theology but also arguing that religion provides a needed
corrective to the misuse of philosophy which, when left to its own
devices, tends to lay claim to the unrestricted use of its principles
(such as PSR) whereas the appropriate restrictions are typically
evident to the theologian (Crusius 1747: SS32).



Crusius' ethics is characterized by the principled separation of
the will from the understanding as distinct powers, and a
re-orientation of his moral theory with respect to the former. The
human will depends on the understanding to supply it with ideas in
accordance with which it acts, but Crusius is clear that the will is
not solely determined to its action through some cognition (i.e., of
perfection) in the act itself; rather, the goodness of an action
consists more generally in its being conformable to the will (Crusius
1745: SS26; Schneewind 1998: 447), and in any case the human will
is always free to act or to omit to act in accordance with the
understanding's ideas. The human will is possessed of three
basic desires--the first is for our own perfection, in accordance
with which the talents of the intellect among others are promoted
(Crusius 1745: SS117); for unification with objects perceived as
perfect, from which proceeds a drive to moral love through which we
desire to join with other rational beings without any further end
(Crusius 1745: SS125); and finally, the desire to recognize a
divine law which, despite its abstract-sounding name, is identified by
Crusius with the phenomenon of conscience (*Gewissenstrieb*).
It is through conscience that we are able to recognize the divinely
given moral law (Crusius 1745: SS132), and conscience thereby also
discloses our dependence on God as divine lawgiver (Crusius 1745:
SS165). As such, conscience supplies us with a motivation to
obedience where, according to Crusius, this obedience constitutes an
essential component (the "form") of virtue (Crusius 1745:
SS177). A derivation of our duties thus depends on a consideration
of God and His aim in creating the world, which Crusius identifies as
*all* human beings' attainment of virtue, as opposed to
knowledge or happiness in its own right, through their free actions
(Crusius 1745: SS213). On this basis, he proceeds to derive duties
to God, to others, and to the self (for discussion, see Schneewind
1998: 452-6).


## 6. Women and Other Under-Represented Thinkers



*(Note: Treatment of these figures has not been integrated into the
foregoing solely for the convenience of those interested primarily in
their contributions.)*



A variety of circumstances--religious, political, and
social--conspired to give women limited opportunities to engage
in and with the contemporary intellectual culture, even compared to
their French- and English-speaking contemporaries. The German-speaking
lands of Europe lacked a major cosmopolitan centre, like London or
Paris, to germinate progressive ideas and to propagate those developed
abroad. Moreover, the fact that, in spite of Thomasius' and
Wolff's efforts, German intellectuals continued to publish (and
teach) in Latin through the first half of the eighteenth century,
meant that women's access to these ideas remained limited. There
were a handful of notable attempts by reformers (including Francke) to
redress the general oversight of girls' education, but by and
large their education was a private matter and in any case guided by
the traditional conception of women's threefold
*Bestimmung* as *Gattin*, *Mutter*, and
*Hausfrau* (wife, mother, and housewife).



Despite these substantial obstacles, however, women did engage with
the figures and debates of the time, and indeed they contributed in
various and integral ways to the history of German philosophy
throughout the eighteenth century. Similar to the British and French
contexts, women in Germany exerted an important influence on
intellectual culture directly through the publication of conventional
treatises, but also indirectly through their correspondence with
well-known philosophers, through provoking and mediating intellectual
disputes, and (particularly in the second half of the eighteenth
century) through hosting salons that attracted leading philosophers
and scientists, among others. And, likewise comparable to the British
and French contexts (cf. O'Neill 1997), these contributions have
been widely overlooked in subsequent histories of German philosophy,
both for familiar reasons having to do both with the narrowness of the
conception of the philosophical canon (Shapiro 2016), but also due to
the concerted efforts among nineteenth-century German academics to
exclude women from the academy (Ebbersmeyer 2020).


### 6.1 Women and the Thomasian Philosophy



Women played crucial roles in the conception, refinement, and
popularization of the key ideas and systems of the German
Enlightenment, as can be seen by considering their contributions to
and connections with the two major early philosophical schools of the
period already discussed: the Leibnizian-Wolffian and the
Thomasian(-Pietist). With respect to Thomasius, it should be noted
that he makes quite clear himself that his intention in publishing his
works in logic and ethics in the vernacular was to reach a wider
audience, including women. Thus, the subtitle of his *Introduction
to the Doctrine of Reason* indicates that it will show



> 
> 
> in an intelligible manner [how] to distinguish the true, probable, and
> false from one another and to discover new truths, all without
> syllogistics, for all reasonable people of whatever estate or gender
> they might be.
> 
> 
> 



Among those women impacted by Thomasius' logic is Dorothea
Christiane Erxleben (*nee* Leporin, 1715-62), who
would later receive the first doctorate in medicine in Germany from
the university in Halle in 1753. In 1742 she published a treatise
entitled *Grundliche Untersuchung der Ursachen, die das
weibliche Geschlecht vom Studiren abhalten* (*Rigorous
Investigation of the Causes that Obstruct the Female Sex from
Study*). While Erxleben there draws on a variety of sources,
including Wolffian thought (cf. Stiening 2020), she makes good use of
two aspects of Thomasius' logic, namely, his
practically-oriented account of *learnedness*, and the doctrine
of prejudice presented in the concluding chapter (cf. Dyck 2021c). So,
in the *Rigorous Investigation*, Erxleben defines learnedness
("*Gelehrsamkeit*") as



> 
> 
> *a grounded knowledge of such necessary and useful truths whereby
> the understanding and will, and consequently true human happiness, are
> improved*. (Erxleben 1742: SS21 [2019: 44]; italics in
> original)
> 
> 
> 



Proceeding from this, she contends that it is important that and
entirely possible for women to be able to attain such learnedness for
sake of the concerns of ordinary life.



Further, Erxleben identifies the widespread conviction that the
attainment of learnedness is unsuitable for women as the result of
prejudice, of which Erxleben distinguishes four principal types: that
women are unsuited (in virtue of their natural capacities) to attain
learnedness; that its attainment could not be useful for them; that
learnedness could only be misused by women; and that women would only
seek to attain learnedness to distinguish themselves from their peers.
By way of rebutting these prejudices, Erxleben draws on an array of
sources, including theological, philosophical, and medical
authorities, and argues generally that whatever disparities might
currently obtain between the apparent talents and achievements on the
part of each sex are not the result of a difference in natural
capacities but instead only evidence of the salutary effect of
education on the human being (cf. Erxleben 1742: SS71).


### 6.2 Women and the Leibnizian-Wolffian Philosophy



With respect to the Leibnizian-Wolffian philosophy, there is
significant evidence of women's extensive engagement with the
system already at its origins. Leibniz exchanged letters with a number
of women, but his correspondence with his patroness Electress Sophie
of Hanover (1630-1714), who happened to be the sister of
Elisabeth of Bohemia, and her daughter Queen Sophie Charlotte of
Prussia (1668-1705), is particularly significant as it
frequently turned to philosophical topics. In his letters, and his
personal exchanges with "the two Sophies", Leibniz can be
seen to refine and develop key doctrines, including his conception of
substance and his attempted theodicy (Strickland 2011: 35-48),
where Leibniz himself claimed that his *Theodicee* found
its beginnings in his conversations with Sophie Charlotte. Sophie of
Hanover likewise supplied Leibniz with one of his favourite pieces of
empirical evidence for the principle of the identity of indiscernables
(when she challenged a courtier to find two identical leaves during a
garden stroll). Sophie of Hanover was no dogmatic Leibnizian however,
as she maintained her commitment to physical influence between the
mind and the body, and hosted controversial figures such as Francis
Mercury Van Helmont (1614-1699) and John Toland
(1670-1722) at her court. It is, however, debated whether Sophie
shared the materialist views of these thinkers when it comes to the
mind (de Careil 1876; Strickland 2009 and 2011: 49-64) or
instead upheld a metaphysically agnostic view regarding the nature of
the soul (Leduc 2021).



As for the other founder of the Leibnizian-Wolffian philosophy, Wolff
does not seem to have been similarly influenced by interaction with
women in the development of his system. Through adopting the
vernacular for his initial series of textbooks, however, he did at
least indirectly contribute to making the latest innovations in
metaphysics, ethics, politics, and physics accessible to a wider
literate audience including women. Indeed, this hardly seems to have
been an undesired consequence as, at one point, at the urging of the
Saxon nobleman and Wolffian devotee Ernst Christoph Graf von
Manteuffel (1676-1749), Wolff drafted the beginning of an
introduction to Wolffian philosophy intended specifically for women
(cf. Ostertag 1910). In the 1740s and 1750s in particular, Wolffian
philosophy had gained such a following among women of society that one
commentator quipped that it was as if "an actual
lycanthropy" had broken out (Edelmann 1740: 108). Among those
women so influenced was Emilie du Chatelet
(1706-49), who made use of foundational Wolffian metaphysical
principles in her presentation of Newton's physics in her
*Institutions de physique*--Wolff and du Chatelet
engaged in correspondence for a time, and he commended her mastery of
his system to others and appraised her as a more talented philosopher
than her companion Voltaire.



In addition to du Chatelet, a number of women took up the task
of defending and developing Leibnizian-Wolffian ideas. None were more
active in this than Luise Adelgunde Viktorie Gottsched
(*nee* Kulmus, 1713-62), whose husband Johann
Christoph
 (SS4.2
 above) was a Wolffian disciple who made contributions to philosophy
(metaphysics and aesthetics), as well as to literary theory and the
development of German letters. In virtue of her ambitious education
(especially in languages), Luise Gottsched contributed extensively to
Johann Christoph's efforts to promote German letters and
theatre, and was a prolific translator, both in the context of her
husband's ambitious projects and in her own right. Thus, she
made substantial contributions to Johann Christoph's
translations of Leibniz's *Theodicee* (J. C.
Gottsched 1744) and of Bayle's *Dictionaire historique et
critique* (1741-44) (for other philosophical translations,
see Brown 2012). She also translated *Reflexions nouvelles
sur les femmes* (1727; L. A. V. Gottsched 1731) by the Parisian
*salonniere* Anne-Thesese, Marquise de
Lambert and produced a translation of and an original response to
Madeleine Angelique Poisson de Gomez's *Le triomphe de
l'eloquence* (1730; L. A. V. Gottsched 1739), which
emphasized the importance of education (including philosophy) for
woman's cultivation of virtue.



Another notable figure in this respect is Johanna Charlotte Unzer
(*nee* Ziegler, 1725-82), who was raised in an
intellectual family in Halle: her uncle J. G. Kruger
(1715-59) was a well-known Wolffian scientist, and
Baumgarten's student G. F. Meier was a close family friend.
Unzer herself would become a renowned poet, though she produced a
highly original philosophical contribution to Wolffian thought in her
*Grundriss einer Weltweisheit fur das Frauenzimmer*
(*Outline of a Philosophy for the Lady*) of 1751. In that text,
Unzer seeks to present the doctrines of Leibnizian-Wolffian logic and
metaphysics in an aesthetically perfect manner, often making use of
poetry to provide a moving illustration of an otherwise abstruse
theorem. In the process, Unzer grants German women access to the most
challenging and controversial philosophical debates of her time
(including Wolff's account of scientific reasoning, the
challenge of materialism, and the Leibnizian doctrine of monads) with
the express intention of equipping her female readers to engage in
speculative and scientific investigations themselves. At the same
time, she offers a dynamic revision and re-orientation of the Wolffian
philosophy which, significantly, attempts to carve out a space for the
(as yet unfounded) discipline of aesthetics (Buchenau 2021).


### 6.3 Anton Wilhelm Amo



A final figure worthy of mention in this context is Anton Wilhelm Amo,
the first African-born professor of philosophy in Germany. Amo was
born in Axim in present-day Ghana around 1700, but was brought to the
Netherlands as a small boy in 1707 through the Dutch West India
Company. Shortly after, he was given to the young Anton Ulrich, Duke
of Wolfenbuttel-Braunschweig, and baptized on 29 July 1708. Amo
evidently worked as a servant in the Duke's court in
Wolffenbuttel, though he would also receive an education which
prepared him sufficiently for study at the Friedrichs-Universitat
in Halle, where he matriculated on 9 June 1727. There, Amo studied
philosophy and law, and it is reported that he presented a (now lost)
disputation in November 1729 entitled *De jure maurorum in
Europa* (*On the Rights of Moors in Europe*), in which he
contended (according to a contemporary account) against the legality
of slavery in the Holy Roman Empire given that the privileges granted
to African kings by the (old) Roman Emperor meant that they were
vassals of the Empire, and entitled to consideration under the
law.



Amo matriculated at the university in nearby Wittenberg the following
year, and was promptly awarded a *Magister* in philosophy.
While in Wittenberg, Amo wrote a dissertation, entitled *De humanae
mentis apatheia* (*On the Impassivity of the Human Mind*)
in 1734, which qualified him to teach, and later in the same year he
supervised a dissertation which he is also thought to have had a hand
(at least) in writing (Menn & Smith 2020: 68-71). Amo would
return to teach philosophy at Halle, and in 1738 published a
wide-ranging manual for his philosophical lectures, *Tractatus de
arte sobrie et accurate philosophandi* (*Treatise on the Art of
Philosophizing Soberly and Accurately*). Not long after, however,
Amo applied for a position at the University of Jena, claiming
indigence, and was granted permission to lecture there in 1740. For
reasons that we can only speculate about, Amo would request passage on
a ship to return to Africa in 1746 (Menn & Smith 2020: 38), and it
was in Axim that a Swiss doctor would report encountering Amo in the
early 1750s. Amo is thought to have died not long after.



In his principal philosophical work, the dissertation on
*Impassivity*, he argues against the claim that the soul can be
endowed with a passive faculty of sensation, a position he identifies
as stemming from Descartes (Amo 1734a: 13-14 [2020: 179]). Amo
understands the human mind to be a species of spirit, which is purely
active and immaterial. Were the mind to be endowed with a capacity to
sense, it would have to be able to receive ideas, and in one of three
ways: by "communication" (i.e., in the manner that fire
"communicates" its heat to an object), by penetration
(i.e., through interposition of another entity), or by direct contact
(Amo 1734a: 5 [2020: 161]). Amo argues that it is impossible to
conceive of the mind receiving ideas in any of these ways as it would
violate its essence as a spontaneous being and its immaterial nature
precludes transmission through contact (for discussion, see Walsh
2019). Perplexingly, in spite of contending for the soul's
impassivity, Amo endorses the Aristotelian dictum that "nothing
is in the intellect that was not first in the senses" (Amo
1734b: 6). Amo also affirms the mind's capacity to influence the
body (Amo 1734a: 8 [2020: 169]), though without accounting for how he
takes this to be possible or explicitly engaging with the debate
relating to the pre-established harmony. Nonetheless, in his lifetime
Amo was identified by at least one influential historian as a Wolffian
thinker (Ludovici 1738: SS202).