## 1. Life and Works



Gomez Pereira's biography is largely unknown. Only a few
data have been extracted from the Prologues of his books and from some
legal documents discovered in his hometown Medina del Campo (Alonso
Cortes 1914: 10; Gonzalez Vila 1976: 95-96). He
was a prestigious doctor who practiced his profession in his own town,
which at that time enjoyed great prosperity as a center of commerce.
His medical reputation may have gone beyond the limits of Medina del
Campo since he was summoned by the court of Madrid to look after the
health of the Infante, the future Charles II, son of Philip II. The
origin of his family is uncertain (the surname "Pereira"
indicates that its origin was probably in Galicia or Portugal). It
seems that his family was in trade and had a favorable position.
Because of this professional activity it has been suggested that
Gomez Pereira came from a family of Jewish
"conversos" (Gonzalez Vila 1976: 96-97;
Rodriguez Pardo 2008: 195-199).



The young Pereira was sent to study Arts at the University of
Salamanca, where a profound pedagogical renewal was just then under
way (Munoz Delgado 1964: 75-89; Valverde 2019: ix). Among
the professors whose lectures he attended we must pay particular
attention to Juan Martinez Guijarro and Juan de Oria. The first
came from the University of Paris and developed at the University of
Salamanca new teaching methods in the field of logic and natural
philosophy. Many years later, Gomez Pereira dedicated one of
his books to him as a sign of affection and admiration for the man who
was in charge of the education of young Philip II and became
Archbishop of Toledo. Also, Juan de Oria - who was later
condemned by the Inquisition and spent his last years of life in
seclusion - lectured on logic and natural philosophy. Oria
probably sparked Pereira's interest in the question of
immortality, since he had great acquaintance with the controversies
which was occurring - especially at the universities of northern
Italy during those years (Munoz Delgado 1987: vol. I,
9-17; Valverde 2020: 242-247).



Gomez Pereira only wrote three books: the *Antoniana
Margarita*, published in 1554, an *Apologia* that he
redacted in 1555 to answer the objections raised against his first
book, and the *Novae veraeque medicinae* of 1558
(Gonzalez Vila 1976: 111-114). As can be seen by the
dates, the publication of his writings was concentrated in a few
years, probably at the end of his life. It is, then, likely that these
writings had many years of reflection, readings and experimentation
probably determined by his profession. The *Antoniana
Margarita*, entitled so in honor of Pereira's parents, is
his best-known work. It is composed in three parts without any
internal division of chapters: the first part, which gives the title
to the entire book, is the largest; the second is a commentary on
Aristotle's *De anima* III, and the third is a treatise
*De immortalitate animorum*. The discourse is arranged in a
sequence of paragraphs whose content is sometimes announced by
marginal notes which are more numerous in the first part than in the
other two. The prose is usually very dense and full of digressions,
many of which are so extensive that they seriously break the thread of
the main argument. The impression of disorder and lack of a previous
expository plan is certainly overwhelming, so that only the
interesting opening of the book, where Pereira introduces *in media
re* the theme of animals' lack of sensory perception, can
attract the interest of the reader. In his *Apologia*, Pereira
summarized and confirmed all the theses previously established in the
*Antoniana*, and took the opportunity to clarify some points of
his own thought, as for example the nature of human soul as a simple
substance that only conceptually can be divided into parts. Finally,
the *Novae veraeque medicinae*, probably published
posthumously, were written following an empirical methodology that
aimed to discover the true causes and the effects of diseases and
affections. For example, against the common opinion of his time and
the criteria of Greek and Arab medical treatises, Pereira explained
fever as a mechanism devoted to restoring a lost equilibrium in the
body.


## 2. Epistemology and Nominalism



Like some other figures of his time, Gomez Pereira took great
interest in exposing the shortcomings and difficulties he encountered
in scholastic natural philosophy. The Aristotelian scheme seemed to
him insufficient, so he directed severe criticism at it for being
unclear or even contradictory in some essential respects, especially
those which had to do with the explanation of life and the
controversial issue of the nature and origin of the soul.



About his own vision of empirical method and scientific research, the
Prologues of his books provide us with enlightening information. In
his *Novae veraeque medicinae* Pereira proclaims that the duty
of a scientist is to use the instruments of logic and experience to
reach the truth, without becoming entangled in the subtleties of
language and sterile sophistry. In this sense, Pereira denounces
Erasmus and his followers for having wasted the intelligence of many
young people who could have devoted themselves to science (NVM: 1a).
Also, at the beginning of the *Antoniana* Pereira rejects the
principle of authority if it is used to replace rational
demonstration. Against those who base their doctrines in Aristotle,
Pereira says: 



> 
> 
> writers of this kind would have had more respect for their readers if
> they had demonstrated what they believed to be true by means of solid
> reasoning. (AM: I.193) 
> 
> 
> 



As we shall see, the epistemology formulated by Pereira in
his *Antoniana* was built on a deep criticism of the philosophy
of Aristotle and scholastic realism.



The *Antoniana* begins by denouncing the incoherencies that
Pereira finds if we admit that animals and humans share sensory
perception. These inconsistencies are based on an erroneous analysis
of the process that leads from the images to the mental concept. In
this process two elements need to be present. First, we receive some
*species* from the external objects through our own
sense-organs. However, these *species* are not yet properly
sensations; to get these last some *animadversio* is also
necessary: 



> 
> 
> Once our sensory organs have been fashioned, in accordance with what
> is due to happen, by a visual image or something corresponding to a
> visual image, human beings should still not be called
> 'sentient' unless they turn the acuteness of their mind
> upon the object they want to recognise. (AM: I.273) 
> 
> 
> 



From sensation thus configured, the mind which *pays attention*
to those *species* builds, at a higher cognitive level, the
*notio* of the object (AM: I.275).



Now, Pereira emphasized that all this is a process in which multiple
instances can be differentiated only conceptually; there is a unique
subject of this process: the entire soul, which first pays attention
to an object and later constructs the notion of it. What is more, the
attention of the soul is nothing other than the soul itself, which
focuses on one object rather than on any other and does it
spontaneously. In other words, its own attention is not accidental,
but what Pereira himself called a *mode* of being: so, the act
of knowing is not *realiter* anything other than the soul
itself (AM: I.295). In this conception, the body does not participate
in knowledge, nor is knowledge different from the soul
(Gonzalez Vila 1975: 28-29). It is likely that
nominalism, during its ephemeral implantation in Spain in the first
half of the sixteenth century, had a decisive influence on
Pereira's thought; he certainly aimed at contradicting the
Realistic notion of St. Thomas about the soul, which assumed that the
soul's faculties are diversified by their acts and, in turn,
their acts are diversified by their objects (Thomas Aquinas, *Summa
Theologiae*, I, q. 77, a. 3). Against this conception, the Spanish
author affirmed that the soul is always equivalent to its acts, so he
ultimately criticized Aristotle for having turned to a group of
differentiated faculties in his description of the cognitive process:
such a plurality was unnecessary.



An example of this criticism can be found at the moment when the
existence of the common sense is rejected in the *Antoniana*
(AM: I.371-373). This is the faculty responsible for processing
the so-called *common sensibles*, that is, those common objects
of perception which are co-incidental to the exclusive objects of each
sense (i.e., motion, rest, number, figure etc.; see Aristotle, *De
Anima*, III, 1-2). In opposition to Aristotle, Pereira
argued that, if the common sense is an organic faculty, so that it
perceives what has been previously perceived by the senses, it would
make the latter unnecessary and we should be obliged to conclude that
nature has created many organs to do what it could with fewer, which
goes against its own principles. It is, therefore, better to maintain
that it is the soul itself, as an indivisible unity, which perceives,
judges and differentiates all the sensibles: the soul is present, in
effect, in all parts of the living body and is affected in a similar
way by all the sense organs.



For Pereira there is no real difference between the sensory and
intellectual faculties. Neither must they be understood as two
different *accidents* of one unique substance, i.e., the soul,
because such a diversity would make impossible to explain how, if the
objects of both sense and intellect are different *realiter*,
they can converge on a single object: it would then be necessary to
appeal for a third power or faculty which would analyze both objects
and, finally, link them. In addition, the unity of the soul would be
broken, because it would be divisible according to the various objects
it can perceive and understand; in this case one could not explain how
it is possible that, since those different objects are processed by
different cognitive faculties, knowledge is always a simultaneous and
indivisible achievement. Pereira emphasized that this is only because
the subject that reaches this knowledge is necessarily one and
indivisible (AM: I.379-381).



Similarly, because of the unity and indivisibility of the soul, the
author rejected the existence of intelligible *species*. For
him, these *species* may not be extracted from
*phantasmata* since these have a corporeal constitution, while
intelligible *species* are immaterial by definition; but our
intellect is unable to generate a spiritual substance from a material
one: God alone is endowed with such a power (AM: I.409). Almost a
century after Pereira had formulated this argument, Descartes resorted
to a very similar one to support his own rejection of intelligible
species as well as of the possibility that ideas can be caused by
bodies (see, for example, Descartes, *Meditationes* AT, p. 41;
about the historical precedents of Descartes' theory see Spruit
1995, vol. II, pp. 379-386: unfortunately, Spruit did not have
access to the *Antoniana*, so he could not introduce Pereira
among the possible influences that Descartes received from earlier
philosophy). For the Spanish doctor it was then much more efficient to
explain the intellectual process on the basis of considering that all
cognitive activity, whether sensory or intelligible, not only depends
on the soul but, in fact, identifies with it.



A new question then emerges: what is the difference between sensory
perception and understanding? Pereira's answer was that there
are not diverse instances of knowledge but rather a unique process
that progressively reaches various stages of refinement. Basing
himself on the Preface of Aristotle's
*Physics*, he examined these various stages through which the
universal concept would pass (AM: I.439-441). This concept can
be confused or distinct: the confused concept is that which covers a
complete genus without any distinction of the *species*
contained therein, while the distinct one is precisely that which
defines the designated object with all the categories that belong to
it. There are then two forms of knowledge: one of them is less subtle
because it rests upon the mere assertion of the existence of an
object, and the other is subtler because it distinguishes with clarity
all the elements that are present in it. Given the nature of our own
cognitive potentiality, it is always easier to have access to the
first type of universal cognition; only through effort and exercising
shall we be able to achieve a greater determination in our own
understanding.



To illustrate this cognitive progression, Pereira explained how we can
achieve the abstract notion of substance: 



> 
> 
> If I want to understand the substance of a square white wall, I turn
> my mind away from thinking about whiteness, and quantity, and shape,
> and location, and when it was built, and all the other individual
> circumstances connected with the wall, every one of which I had
> recognised beforehand, either by means of my external senses, or
> conceived earlier abstractly in my imagination, and I draw forth
> cognition of something I have never perceived sensorily, namely, the
> subject of these things. (AM: I.445) 
> 
> 
> 



This process is accomplished by us spontaneously. Pereira said that it
is simply a quality that belongs to our soul by nature and allows us
to extract species from genera. We do all this by ourselves and in
ourselves, since, as he repeatedly emphasized, the intellect, the act
of thinking, and the object thought are the same, i.e., the unique and
indivisible human soul (AM: I.455; see Gonzalez Vila 1975:
28-30).



Pereira's nominalist position rests on this basis. The question
of whether universals are or not substances is elucidated by
explaining the universal concept as a connotative term which exists
only in the sentences formulated by our own mind. The soul understands
that the singular elements that can constitute a genus or a species
have similar characteristics, and thus it regards them all as a unity
and this unity as a universal concept. Applying this doctrine, Pereira
directed his criticism to certain metaphysical concepts that were
meaningless and unnecessary for him. Such is the case, for example, of
the scholastic difference between essence and existence. Against St.
Thomas, he affirmed that these two concepts are not different
*realiter* but only conceptually, and this because 



> 
> *... aut essentia erit ens, et sic ens et essentia non
> distinguentur, quod probare nisi sumus. Aut non erit ens, et sic non
> ens intrasset entis compositionem, quod implicat.* (AM: I.490)
> 


That is:



> 
> ... either essence will be a being, and thus a being and essence
> will not be different from one another, (which [we cannot] prove
> unless we exist) or it will not be a being, and thus a being would not
> have entered the make-up of the thing it is embracing. (AM: I.491)
> 



Nor did Gomez Pereira accept the concept of prime matter. The
procedure which Aristotle followed to conceive this concept was none
other than analogy, because prime matter is not accessible to the
senses. It is something that remains as an immutable subject in the
transition from one form to another one; for instance, if a new form
must be induced during the process of generation, then the natural
dispositions required for the formation of the new living being must
be precedent and remain during all this process; those dispositions,
inaccessible to sensory perception, are prime matter, which lacks any
positive nature. Hence Aristotle pointed out in *Metaphysics*
VII that it is not a *quid* or a *quantum*, or any other
genre of predicates (see *Metaphysica*, VII, 3,
1029a6-29). Against this theory, the author of the *Antoniana
Margarita* argued that in the process of natural generation it is
observed not only that the material part of the compound disappears,
but also the formal one, so if the sentence *ex nihilo nihil
fieri* is adopted by the Aristotelians for affirming the necessary
permanence of matter, the same should be said with respect to the
form, since neither the form nor matter can turn into nothing or be
generated from nothing: this means then that also the form would exist
in a temporal continuum (AM: I.549). In Pereira's opinion, this
problem can be easily solved if we consider that the elements are the
basic materials of nature. They can perfectly play the role of matter,
and there is no problem in the fact that the elements are also subject
to mutation and even annihilation, because, ultimately, they are under
the influence of qualities which are contrary to their own
consistency: so when these qualities have a strong presence in them,
this always leads to their destruction; but, on the contrary, whenever
the primary qualities appear in the right proportion, the same
elements are generated again.


## 3. Psychology


### 3.1 Nature of the soul



Pereira's epistemology follows from a theory of the
soul whose basic premises are simplicity and indivisibility
(Gonzalez Vila 1975: 22). His own vision of the rational soul
led him to object to the philosophy of Aristotle, as well as to give a
response to the question of whether the human intellect can perform
its own activity without the support of the body. Pereira's
reply was a categorical yes: in fact, given his own epistemological
premises, knowledge is possible only if it is identical with the
substance of the soul itself. To demonstrate this assertion, the
author addressed some issues that had been present in the debate about
the nature and destiny of the soul from the Middle Ages (see Nardi
1958: 365-442; Kristeller 1979: 181-196; Valverde 2019:
35-55).



In the first place, the problem of the soul's indivisibility had
aroused an important debate within Aristotelianism. Aristotle himself
had already denounced at the end of Book I of his *De Anima*
the absurd consequences of considering that the soul has parts
understood as substantially different: if the soul is the principle
that unifies the body, it can in no way be divisible itself; if not,
we should have to find another superior principle and so on to
infinity. Notwithstanding this assess, there is no doubt that
Aristotle also spoke of the different functions exercised by the soul
through its different faculties: thus, it was inevitable that the
unity of the soul reappeared once again. This issue had been widely
discussed since the Middle Ages but remained still debated among many
Renaissance Aristotelians. The subtleties (*distinctiones*) in
the interpretation of the thought of Aristotle became increasingly
complex, giving rise to an intricate tangle of arguments and
counter-arguments difficult to follow even for the experts (see Di
Napoli 1963: 339 ff.; Schmitt 1983: 13-42; Bianchi 2003a:
133-172).



Linked to this question was another topic also discussed among the
Aristotelians: are there several substantial forms in a single
compound? The different responses to this question had a particular
impact on the debate over the connection of the intellectual soul with
the body. Two main positions can be easily distinguished here: there
was a unitary position based on the thought of St. Thomas, for whom
the intellective soul is the only substantial form present in human
beings, having in itself the derived potentialities of the vegetative
and sensitive souls; the position contrary to this had as a pattern
the philosophy of Averroes: in this case many - professed
Averroists or not - admitted the existence of more than one
substantial form in the same compound in order to explain the link
between the human soul and the body, as can be seen in great figures
of medieval and Renaissance Aristotelianism such as John of Jandun,
Nicole Oresme, Paul of Venice, Agostino Nifo and later Giacomo
Zabarella. Zabarella summarized this position by pointing out that the
intellectual soul may in no way be attached directly to prime matter:
its own complexity requires a high level of organization in the
subject matter so that it can serve as an appropriate instrument for
the powers that the human soul is capable of exercising. For this
reason, our soul needs a preliminary compound with its own substantial
form (Zabarella 1590 [2016: vol. II, pp. 897]; Park 1988:
464-484).



In this debate Pereira wanted to intervene formulating a discourse
whose principal aim was to resolve those difficulties which were
inherent in the relation between the soul and the body. This discourse
was clearly linked to the theoretical assumptions of his time, but it
had in addition traits of certain originality which has gone alas
largely unnoticed. The author of the *Antoniana Margarita* put
his finger on the deficiencies of the Scholastic-Thomist philosophy
when it was applied to demonstrate the immortal nature of the human
soul. In this sense, he clearly assumed that the criticism of the
Alexandrist Aristotelians, and in particular of Pietro Pomponazzi, was
essentially correct (Pine 1986: 124 ff.; Perrone 1999:
xlvi-lxvii). Pereira concluded that assuming that the rational
soul is potentially capable of exercising the activities related to
vital functions implies recognizing that it is linked to the body.
Thus, given the premises established by Aristotle himself in his
*De generatione animalium* (II, 3), the origin of that soul
must be found in the same process of natural generation that gives
rise to the living body, but this process is essentially material. For
Pereira, then, if we really want to save the immortality of the soul,
we must radically separate it from all activity that is related in one
way or another to the body. He accepted the consequences of the
dilemma that Pomponazzi had established in his *De immortalitate
animae* (1516): if the soul has the body as its own substratum
(*ut subiecto*) or cannot operate without the support of the
body (*ut obiecto*), it is inseparable from it, being then
perishable (see Pine 1986: 55-123; Kessler 1988:
500-504). It can be said that, to a great extent,
the *Antoniana Margarita* was conceived to give a satisfactory
answer to this unavoidable syllogism (see Valverde 2017:
541-553). Pereira tried to show that the rational soul has
nothing to do with the body because it is a simple and independent
substance dissociated from all those vital functions that have the
body as their object or as their substrate: these functions belong
then to a psychic principles different from the intellect: 



> 
> 
> In their workings, external as well as internal, all forms except the
> rational soul make use of the ways their whole is arranged, as
> instruments, and without these they could do nothing. (AM: I.739) 
> 
> 
> 



The forms of brute beasts use heat, cold, wetness, and dryness, to
feed and preserve the whole, of which they are intrinsic parts, but it
lacks unity precisely because of its intimate connection with the
parts of the body that perform the vital functions. Therefore, this
soul is drawn from the very power of properly organized matter.



For Pereira, the rational soul is completely different. Its
indivisible nature is alien to the generative process that gives rise
to a living body. Thus, in Pereira life and spirit are sharply
disconnected. This is the only way to demonstrate the immortality of
the soul. To achieve such a demonstration, he believed that, as
principle of apprehension and knowledge, the soul has to comprehend in
itself all the episodes included in this activity. What is more, the
substance of the soul is always its own activity. Now, if this is so,
the question is why the soul is not continually thinking. Gomez
Pereira's answer was that *attention* is what determines
both the perception of objects which can be perceived sensorily and
the self-perception of the soul itself; the latter as well as the
former depend on the will of the soul: consequently, they are not
continuous (AM: II.1071). If it were so, we could not perceive
anything else. Moreover, the necessary condition for self-perception
is some kind of "awakening" that the soul experiences from
external objects: only after this excitement does the soul become
aware of itself, that is, of its own existence. The final conclusion
of Pereira is then: 



> 
> 
> If this notion is going to precede, it will be able to serve no useful
> purpose other than recognition that there is a particular antecedent
> from which the soul may later elicit a consequence: namely, that it is
> self-aware. The reasoning will go as follows. *I know that I know
> something: whatever knows, exists: therefore I exist* (*nosco
> me aliquid noscere, et quicquid noscit est, ergo ego sum*). (AM:
> II.1075) 
> 
> 
> 



Once the soul has known its own affection, it is able to reflect on
itself and discover itself as existing. This is a single process in
which two moments must be distinguished: in the first act the soul
knows the fact of being affected by something, whereas only in the
second does it know itself as an independent entity, with autonomous
existence. Now, the immediacy with which the soul reaches the
consciousness of this existence shows that for Gomez Pereira
this is not a deductive development, but a pure intuitive act that has
a previous formal factor: the awareness of the affection is, in
effect, "*quodam antecedens cognitum*" necessary to
verify that the soul "*seipsam noscit*".



The above expression "*nosco me aliquid noscere, et quicquid
noscit est, ergo ego sum*" is not the final sentence of
the *Antoniana Margarita*, since Gomez Pereira will
formulate new arguments *pro immortalitate*, but it can be
considered as the true culmination of all the discourse that the
author has directed to prove the immortality of the soul. This
discourse represents the central nerve of the work to which the other
contents, and especially the doctrine of animal insensitivity, are
secondary derivations. Many scholars have argued that animal
automatism represents the genuine motif of the *Antoniana*,
probably because of its originality, but we should not confuse
originality with logical priority. Underneath the amalgam of contents
and the diffuse and often disordered prose of the author of
the *Antoniana*, a well-structured reasoning was present, in
which three stages can be distinguished (Gonzalez Vila 1975:
22.): 


1. The nature of the act of knowledge requires an indivisible
principle, so that only the soul, the unique indivisible principle in
man, knows; the body does not participate in sensory knowledge, not
even as a tool; therefore, the soul, in its main functions (which are
cognitive) enjoys complete independence and full operational
self-sufficiency regardless of the body.
2. This operational independence logically founds the ontological
independence that allows the survival of the separated soul. Although
Pereira does not deny the "corporeal" conditioning factors
to which knowledge is subject, as evidenced by experience, he
recognizes that the soul is weighed down by the body in its cognitive
operations, so the body restricts the original and absolute cognitive
spontaneity of the soul.
3. Once the operating-ontological independence of the soul is
asserted, and consequently its separate subsistence, the perpetuity of
this subsistence does not involve any difficulty, since in the soul,
which is indivisible, there is no intrinsic principle of
corruption.


### 3.2 The Body-soul compound



This conception adopted by Pereira to explain the integral unity of
the rational soul needed to be developed to explain the integral unity
of the human being. Many of his statements, both in the
*Antoniana* and in the *Apologia*, pointed out that the
human being is not only the soul, but the conjunction of a body and a
soul (see, for example, AM: I.687, I.697, II.1077, II.1149). In fact,
he never abandoned the formal relationship that the rational soul has
with regard to the body (see Gonzalez Vila 1975: 41). However,
the concept of form used by Pereira permitted him to speak of a
plurality of forms in a single subject (as many Averroists defended:
see above). For him, the *unity* of a compound is not given by
the *uniqueness* of a substantial form, but by the hierarchy of
several forms under a superior one that gives the compound its
ultimate denomination. In a human, who is the most complex being of
creation, there would be a compound of compounds. Therefore, the
rational soul is not the only substantial form in him, although it is
the only *human* form since it crowns that hierarchy of forms
and confers to the *whole human being* his nature and
denomination. Pereira defended what can be considered a
*dynamic* hylomorphism which was surely built on his own
biological experience as a doctor. However, the body-soul union of
which the Spanish physician spoke in his *Antoniana* can hardly
be considered substantial *sensu stricto*, mainly because in
his book there is no detailed explanation of the relation of the soul
to the body, or of what kind of union there is between two natures so
different in themselves. For him it is a *factum* that in human
beings these two natures converge, but he failed to explain this
question - probably for the sake of a coherence that was perhaps
impossible.




It is curious that many of his contemporaries tried to respond to the
challenge of proving the immortality of the soul by appealing to
coherence, precisely when the Alexandrists emphasized that the
coherence of Aristotle was placed in mortality: every substantial form
is born and perishes with the compound to which it gives the
essence. Pereira was then not original when he tried to respond to
Pomponazzi's mortalist thesis by resorting to an alternative
coherence based on the radical separation of body and mind. But, in
this attempt, he showed, probably as no one before, that the
hylomorphic explanatory scheme applied to the nature of the human
being led to an unavoidable crossroads: one path ended in an integral
materialism, the other in a strict dualism. Those who chose this last
road, as Pereira undoubtedly did, had a peremptory question before
them: what is the body for? For Pereira the body was a datum of
experience whose negation would have been contrary to the principles
upon which he wished to sustain his work, i.e., experience and logical
coherence. His response came through the allegory of an imprisoned man
(AM: II.1067). The soul is like a man inside a reticular sheath. This
man cannot know anything at all if he is not "awakened" by
the blows that fall on the surrounding sheath from outside. Such blows
or affections produced by external realities are necessary for the man
wrapped in such a sheath to awaken and know, but they are not enough
to explain knowledge itself. Thus, for Pereira the body is a kind of
"alarm clock" of the soul. This corporeal affection is
required *pro statu isto* (i.e., the state of union body-soul)
as *conditio sine qua non* of human understanding. But it is no
less true that for Pereira the soul outside this sheath-jail would be
permanently awake and would possess a more perfect knowledge of itself
as well as of the other objects. Unfortunately, Pereira did not
explain at any time why the soul has to be in such a deplorable state:
forgetful of itself, and aware only when it is unpleasantly excited by
external stimuli. The tone in which Pereira referred to the situation
of the incarnated soul shows us the most pessimistic version of an
anthropological dualism: the knowledge that the soul is capable of
achieving in this life is only a pale reflection of the one it can
reach in the other. If, as Pereira seems to think, the soul is
essentially self-consciousness, this nature can be reached here only
indirectly, and for a limited time. But Pereira told us nothing of the
metaphysical framework that would be needed to explain what universal
order allows a reality of a higher nature to be restricted in this
way. If the death of the compound involves the reunion of the soul
with its true condition ("*corrupto carcere statim in totum
expergiscetur*"/"once his prison was destroyed he
would be completely awake" AM: II.1068/1069), why should it
suffer the unfortunate restrictions to which it is subjected in the
body? Although he wanted to deal with the issue of the soul's
immortality from the point of view of natural reason, in the end it
was necessary to transcend the physical realm to give a full
explanation of the fact that two natures as different as the spirit
and the body cohabit in human beings.


## 4. Animal Mechanism



The beginning of the *Antoniana* is an extensive discussion
aimed at demonstrating that animals do not have the faculty of sensory
perception. His argument is easy to sum up: if animals had the ability
to perceive objects and were able to behave in one way or another
depending on this perception, then we should have to grant them not
only sensory perception, but also the faculty of reasoning. What is
more, it would be necessary to conclude that they have an indivisible
and immortal soul, as humans do. Pereira himself recognized that such
a thesis could seem surprising, since it was generally accepted that
beasts had been endowed with the faculty of sensory perception (AM:
I.191). The author was right to believe that to his contemporary
reader a thesis that denies the existence of sensory perception in
beasts might seem not only a striking novelty, but also something
which contradicted common experience and the principles of
Aristotelian philosophy. Without going into the controversial question
of whether Aristotle accepted or not the existence of certain traces
of intelligence in animal behavior (see Newmyer 2011: 6-10),
there is no doubt that he attributed the sensitive faculty, in
different degrees of complexity, to animals. In the *De Anima*,
without going any further, Aristotle clearly said: 



> 
> 
> now all animals have one sense at least, viz. touch, and whatever has
> a sense has the capacity for pleasure and pain and therefore has
> pleasant and painful objects present to it, and wherever these are
> present, there is desire, for desire is just appetition of what is
> pleasant. (*De Anima*, II, 3, 414b3-5)
> 
> 
> 



But, if the boundary between humans and animals is located at the
limit between sensory perception and the intellect, precisely because
this limit is far from being well-defined, it is difficult to
determine with precision the ontological difference between men and
animals, to the extent that one can find some cases of true bestiality
among humans: these cases are certainly rare, but not as rare as those
men who are capable of living according to virtue and science (see
Bianchi 2003b: 63-100). This is the context that explains much
of the content of the *Antoniana*. In the opinion of its
author, those who recognize that any animal perceives what seems to it
desirable or harmful, and then acts accordingly initiating a movement
in pursuit of it or escaping from it, are not only obliged to grant
them a sensory faculty with a discriminating power, but even
rationality and thought (AM: I.199). Moreover, given that Aristotle
also distinguished an intellectual faculty devoted to apprehending
simple objects and another one which can deduce the complex from the
simple (so that one can built a true or false proposition from the
connection of terms), then if we concede the first power to animals,
we must also concede the second, since 



> 
> 
> those who maintain that brute beasts recognize the presence or absence
> of an enemy or a friend are forced to acknowledge that they are
> forming mental propositions. If this is not so, let them explain how
> one recognises the existence of an enemy, and they will find no answer
> other than the formation of the foresaid mental propositions. (AM:
> I.203) 
> 
> 
> 



Furthermore, if the animals are capable of knowing the world through
sensory perception, nature would have been very cruel for making them
suffer all they suffer, for example, at the hands of men. And, given
that certain species of animals can pre-empt the arrival of cold
winter and shelter or run away from it, we must grant them also some
faculty of prediction; but, if they can predict the winter, they will
also be able to have knowledge of death and, just like human beings,
they will worry about the future of their souls (AM: 1.215).



We might also grant them the knowledge of universal concepts. As
Aristotle says, once the premises are established and known, it is
necessary to deduce from them a conclusion: for example, if beasts
know that *this* fire burns, and that *this other* also
burns, and they run away from whatever fire they can perceive, they
must have formulated the proposition "all fire burns." In
this case, they have an indivisible soul, since only with an
indivisible soul can one achieve the knowledge of any object as a
whole. For, if we accept that the animals have a divisible soul
(*quanta*), they will never reach such global knowledge: an
animal would know through a part of it a part of its object, and
through another, another part, and so it would be unable to reach a
perfect identification of whatever could be in front of it (AM:
I.227).



To avoid such undesirable consequences, which *de facto* put
animals in the same category as human beings, Pereira tried out an
alternative explanation of animal behavior. This behavior and the
diversity of movements observed in animals is due to what he called
some *occultae qualitates* by which visual images
(*species*) coming from outside, or certain affections that
occur in the *phantasmata* that stay in the front of the brain
(*occiput*) set the animal in motion by activating its nervous
system (AM: I.253). In the case of human beings, who, like animals,
are also exposed to these *species* and have inside their
brains the same *phantasmata*, there is a real mental activity
which is able to generate their own movements through the knowledge of
the object.



For Pereira, there are three main types of movement in nature. The
simplest is movement of inorganic objects. It is ruled by the
principles of perpetual and invariable motion. This movement is merely
a local one: for example, the attraction of metal to a magnet. The
most complex category is voluntary movement (i.e., the complete
freedom of movement of humans). At the medium level of complexity,
Pereira located what he called "vital movement", which
describes animal movements. Vital movement includes movement caused by
muscular and nervous organs in direct response to interior and
exterior stimuli; this movement does not involve will nor any kind of
spontaneous decision. Notwithstanding this, Pereira said that vital
movement does not consist of invariable movement. Instead, the
complexity of movements that can be observed in animals is the result
of the complexity of the stimuli or forces that can act on them. To
clarify this, Pereira classified four different types of animal
movement: i) movements produced as a reaction to objects that are
present; ii) movements produced by objects that were present in the
past time; iii) movements produced as consequence of some previous
instruction; iv) movements resulting from the so-called *natural
instinct* (AM: I.241). The central core of Pereira's theory
on animal behavior is found precisely in the explanation of these four
types of movement (see Sanchez Vega 1954: 383-387;
Bandres & Llavona 1992: 161; Rodriguez Pardo 2008:
191).



(i) The first type of movement is based on the reaction to objects
that are present. In this case, Pereira formulated an explanation that
embraced a pioneering theory of reflex reaction which involved both
peripherical stimuli and a central organ. The process as it was
described by him consisted of four phases. It starts with the object
that stimulates the sensory organs. This stimulation leads to
reactions in the sensory organs which cause certain mechanical
alteration called by Pereira *species.* The sense of touch
occupies a special category into this explanation model, since in this
sense the process is not activated by means of mechanical alterations
caused by distant object, but by direct physical contact between the
object and the organism, without the intervention of those
*species*. The second phase consists of the transmission of the
alteration in the sensory organ to the brain. This transmission of the
*species* to the brain takes place without any resistance, so
that it spreads along the nerves at an enormous speed. The third phase
is located in the brain and consists of the activation of the areas
where the motor nerves originate (Pereira considered the connections
corresponding to each sensorial modality to have a specific location
in the brain). And finally, the fourth and last phase consists of the
activation of the nerves which gives way to contraction and distention
of the muscles that generates the movement of the different parts of
the animal (AM: I.243-245).



But for Pereira it was evident that, before the same object, the
behavior of an animal could vary and even be contradictory. He
explained such a variety by resorting to a complex interaction of
factors that occur simultaneously. To illustrate this question the
author described the case of an animal that on some occasions drinks
as a reaction to the presence of water and on other occasions does
not, depending on the interaction between the *species*
produced by the water and the current internal state of thirst of the
animal (AM: II.877).



(ii) Another type of movement is that produced by previously present
objects. To explain this type Pereira turned to internal senses, which
he defined as inner cognitive organic faculties. He said that, while
there are two internal senses in man, imagination and memory, in
animals only memory is present. Pereira then developed a mechanical
way of processing information in animal memory which excluded mental
activity. According to him, when an object disappears it leaves a
*phantasma.* These *phantasmata* or traces are stored in
a cell located in the posterior zone of the brain, remaining there in
a passive state. In the absence of the object, those
*phantasmata* can be activated and move from the cell to the
*synciput* which is located in the anterior zone of the brain.
There they produce the same reactions provoked by the *species*
coming from present objects. The author said that the only difference
between humans and animals with respect to the function of memory is
that man can voluntarily cause the movement of the memory traces to
evoke a recall, whereas in animals this movement is due to purely
mechanical stimuli which can come from internal or external origin
(AM: I.251, I.253-255, I.263-265).



(iii) Pereira's third type of movement is produced by training,
which certain animals are capable of assimilating. His doctrine is
developed through the exposition of specific cases of animal training.
For example, Pereira considered the imitation of human language by
birds as a special type of reflex mechanism in which hearing organs of
birds receive voice waves which are transmitted to a soft area of the
brain where they are recorded. When the brain is activated after
receiving some stimuli, it causes a series of muscular movements in
the speech organs that finally reproduce the previously recorded
sounds. In this case, hearing and speech are two sides of a single
process. Another case that Pereira studied was that of birds which can
emit words that have been spoken in the past. According to him, this
is due to the animal memory wherein a voice is retrieved from the
corresponding trace or *phantasma* that is stored in the
posterior area of the brain. When these traces are somehow activated,
they pass to the anterior zone and provoke the production of the same
sounds that created them. But why should an animal emit some words and
not others? The explanation is found in the frequency with which a
determined voice is presented to the animal: the trace of a frequently
repeated voice is more mobile than that of an infrequent one, and then
much more susceptible to flowing in the direction of the anterior zone
(AM: I.263). Another example of training in animals is found in
movements in answer to a master's voice. These movements consist
of approach or escape reactions and the diversity of responses can be
explained by certain voices in the past which have been followed by
the offer of food whereas others have been produced by punishment. In
this case, Pereira explained how the activation of a master's
voice *phantasma* on the posterior area of an animal's
brain generates the mobilization of the *phastasmata* of past
events that were accompanied by such a voice. Here it is important to
note that reward and punishment have a primary role in Pereira's
concept of behavior modification, because they are effective not only
in establishing new behaviors but also in favoring learning by
imitation (AM: I.263-265).



(iv) The fourth and last type of movement in Pereira's theory is
instinctive movements. Pereira attributed these movements to what he
called *natural instinct.* Among the examples he used is the
persecution of the mouse by the cat. Pereira recognized that the
perfection and complexity of these movements are such that, if they
are not carefully examined, they could lead us to the conclusion that
not only do animals have sensations, but that they also possess
thought and reason. However, mere appearances are not evidence or
proof. For example, he described the astonishing action of semen
deposited by the male inside the vulva, and yet, semen does not have
sensory perception. The same can be said of nutritional processes,
wherein the relationships between different organs cause a selection
of some materials and the rejection of others, and neither these
operations are the result of a sensory process (AM:
I.343-345).



In sum, Pereira thought that all these movements might be explained by
turning to two types of causes: *specific causes* and
*generic causes.* The first ones consist of various actions of
the *species* on the receptive organs; that is to say,
environmental stimulation. Generic causes are the functional interest.
Pereira placed these causes under the general term
"nature", which plays a role as a universal regulator (AM:
I.349). This broad generic cause is responsible for animals having
organs adequate to enable them to interact with their habitat. This
also explains the different bodies and types of animals and their
varying capacity to be trained. Nature is also responsible for the
fact that some of an animal's external movements serve as signs.
For instance, a dog's bark or a lion's roar frightens us
and warns us of possible attack. Pereira considered instinctive
movements to include those basic processes related to environmental
adaption, especially the search for food, avoiding danger, etc. These
movements are the result of the interaction between natural tendencies
in the animal and concrete environmental circumstances. In this way,
Pereira explained the perfect harmony between the beast and its
physical, animal, and human surroundings (see Bandre &
Llavona 1992: 163-164).


## 5. Aftermath



The little attention that has been paid to the *Antoniana
Margarita* by Spanish researchers (outside Spain this attention
has been non-existent) has been mainly focused on the impact of the
work especially in post-sixteenth century philosophy, just when its
fortune was linked to the Cartesian philosophy as a possible precedent
of the animal mechanism formulated by the French philosopher (see
Gonzalez Vila 1977: 99-125; Bandres & Llavona
1993: 131-137; Valverde 2019: 55-61). However, a closer
look allows us to verify that in the immediate context of sixteenth
century Spanish philosophy the *Antoniana* had a certain
impact, negative rather than positive. Gomez Pereira himself
introduced in an early reprint of his work the first or at least one
of the first reactions to his book. In this case, the reaction was
solicited directly by Pereira, because he asked his old teacher Miguel
de Palacios, Professor of Theology at the University of Salamanca, for
a critical survey of his book. The *Objectiones* which Palacios
wrote to please his pupil were included in the *Antoniana
Margarita* and accompanied by an *Apologia* where Pereira
summarized and defended all the theses previously
established. Palacios' attitude was that of a professor who
condescendingly reads the work of a good student, not that of a
genuine critic. In any case, these *Objectiones* failed to
identify the central message of the *Antoniana*, either because
the author did not read the work carefully or because he did read it
but did not understand his student's thought. Palacios'
work analyzed some questions which, even if they do not lack some
interest, do not address the core of the work, that is,
Pereira's intention of dissociating the soul and the body so as
to formulate on this basis a demonstrative proof of the immortality of
the human soul. For, even if in the order of the text the thesis of
animals' lack of sensory perception is the first issue
addressed, this was only one of the consequences drawn from the
claimed independence and unity of the human soul. In Palacios'
opinion, however, that was the only significant content of the book,
so he was unable to build a systematic criticism of Pereira's
arguments.



Another notably adverse reaction to the *Antoniana* was
the *Endecalogo contra Antoniana Margarita*, written in
Castilian by Francisco Sosa, a colleague of Pereira who lived in the
same city and probably met him. This work is a satiric fable in which
the animals bring a suit before Jupiter, as a judge, against Pereira
because he has deprived them of genuine sensory perception and
self-movement. Gonzalez Vila emphasizes that the work, beyond
its questionable literary quality and lack of philosophical depth,
serves only to demonstrate that the *Antoniana* had some
popular repercussion (see Gonzalez Vila 1977: 102).



These two books show that the immediate reception of Pereira's
work was adverse and probably disappointing for the author, who could
feel misunderstood and unjustly attacked. In any case, the echo of his
work vanished soon, as evidenced by the fact that during the next
century the references to the *Antoniana* and to Gomez
Pereira himself were very few.



The second period dates from the moment when Gomez Pereira
became the object of the attention of those who saw in him a precedent
of the philosophy of Descartes. The great occasion for this ephemeral
change arose from the French philosopher Pierre Bayle. Before him,
Vossius had already spoken of Pereira as a precursor of animal
mechanism (Vossius, *De theologia gentili*, 1641 [1700: vol. V,
p. 345]). But when Bayle
included Pereira in his *Dictionnaire* (Bayle 1730: vol. III,
pp. 649-656), he gave rise to a debate about the true
originality of Descartes before the unquestionable precedent contained
in the *Antoniana Margarita*. Bayle did not discuss
Pereira's merit as the true author of a primitive version of
animal mechanism, but he thought that the real originality should
nevertheless be attributed to Descartes, because his mechanism derived
from the firm principles of its philosophy, while Pereira had only an
ingenious occurrence without the support of a true system of
principles such as that of Descartes.



From this moment on, the figure of Pereira acquired a relevance like
never before. Even if Bayle tried to show the unmethodical way in
which the doctor of Medina del Campo expressed his doctrine of
animals' lack of sensory perception, the fact is that it did not
take the opponents of Descartes long to spread the suspicion that he
had plagiarized some of the contents of the *Antoniana
Margarita*. This accusation was known to the extent that Adrien
Baillet, the great biographer of the French philosopher, was obliged
to claim that the doctrine of animal mechanism had already been
conceived by the young Descartes before he had the opportunity to know
of the existence of Pereira's book (Baillet 1691: vol. I, p. 51
ff.). However, it has been maintained that neither the chronological
observations of Baillet nor the denial expressed by Descartes himself
of having read Pereira's work completely rules out the
possibility that he could have read Pereira's book in the
Netherlands, where it was probably more accessible than in France.
Those chronological reasons of Baillet were not accepted by many
others, such as Huet, who openly stated that Pereira had clearly
anticipated Descartes in the theory of animal automatism (Huet 1689
[1734: 193 ff.]).



Other references to the work of Gomez Pereira can be found
during the transition from the seventeenth to the eighteenth century,
for example, in the Portuguese Jewish physician Isaac Cardoso, who
edited his *Philosophia libera* in 1673. Here Pereira is placed
on the same level as Valles and Gassendi as a modern atomist
who rejected the Aristotelian concept of prime matter. Even in Leibniz
himself we can find traces of Pereira: in two letters dated on 1711
and 1713 he said he was looking for a copy of the *Antoniana*,
and after having found it, he recognized that the thought of Descartes
was not too different from that of Pereira. Leibniz believed, however,
that the French philosopher had not read his work.



The question of Descartes' debt to Gomez Pereira will be
found again among the Enlightenment writers, as we can see in the
Dictionaries of Calmeto, Moreri, Brucker, etc. (see Bandres
& Llavona 1993: 133-134). In the *Encyclopedia* of
Diderot and D'Alembert, particularly in the article devoted to
the soul of beasts, we may read that Descartes was the first who dared
to treat animals as mere machines, even if Gomez Pereira had
said something similar before him, but he arrived at this concept by
pure chance. The Enlightenment authors echoed the opinion of Bayle in
pointing out that Pereira did not draw his doctrine from any
principle, and therefore his name had scant relevance: he suffered the
saddest thing that can happen to an innovator, "*il ne fit
point de Secte*" (Bayle 1730: vol. III, pp. 651).



One unexpected effect of the presence of Gomez Pereira in the
French erudite elite, even if in a pale way, was the recovery of his
work during the eighteenth century. But, unfortunately for our author
again, this recovery did not involve any serious and detailed study of
his thought (Gonzalez Vila 1977: 109). The unique perspective
adopted to comment on and analyze the contents of the *Antoniana
Margarita* was determined by the notion of their possible
influence on Descartes; moreover, the Spanish writers generally
followed the sentence of Bayle denying such an influence. One of the
most notable exceptions was the Jesuit Juan de Ulloa, who after
refuting mechanism and atomism, said that, in spite of everything, he
was proud of the fact that some of his countrymen, such as Pereira and
Valles, had guided such powerful minds as that of Descartes
(Bandres & Llavona 1993: 134).



This growing interest in animal mechanism and specifically in the
*Antoniana Margarita* was the cause of the second and final
edition of the book in 1749, whose preface and permission generously
praised Gomez Pereira, and lamented the fact that such an
innovator had fallen into total oblivion among the philosophers of his
own land. Unfortunately, this new edition did not remedy the
prevailing ignorance about him, as one can realize by reading the
different works of natural philosophy and the dictionaries produced in
Spain at that time, where there are few references to our doctor and
they seem to come from indirect sources, not from a direct reading of
the text.



This same poverty of references to Gomez Pereira's
philosophy was also present during the nineteenth century, at least
until the moment when, in the context of a debate on Spanish science
which was stimulated by Menendez Pelayo and J. M. Guardia,
among others, the figure of Gomez Pereira was recovered as an
illustrious example of a true scientific tradition, or on the contrary
as an exception in the most desolate desert.



In the case of Menendez Pelayo, whose interest in the
*Antoniana* came from his youth, Gomez Pereira was
considered as an outstanding physician, a great scholar and a true
pioneer of Cartesianism not only from the point of view of animal
mechanism, but also as the first author of the famous *cogito ergo
sum* (Gonzalez Vila 1977: 113). Later the Cantabrian
scholar dedicated a detailed monographic study to the
*Antoniana*, which he first published independently in 1878 and
later as an appendix to his famous work *La ciencia
espanola* (Menendez Pelayo 1887-1888: vol. II,
*Appendix*). Against the interpretative tradition that was
rooted in Pierre Bayle's opinion with respect to the thought of
Pereira, Menendez Pelayo argued that in the *Antoniana*
there is a complete philosophical system based on well-established
principles. The image of Pereira drawn by Menendez Pelayo was
that of a great thinker (comparable to Vives), a sincere Catholic who
was able to reconcile independence with orthodoxy, and someone who
represented the living proof of the freedom of Spanish scientists
under the Inquisition.



Another relevant vision of the Castilian doctor, contemporary with
that of Menendez Pelayo, can be found in the doctor, science
writer and Humanist Jose M. Guardia, who was educated in France
(in fact, the majority of his works were published in the famous
*Revue Philosophique de la France et de l'Etranger*).
Guardia destined an extensive study to the figure of Gomez
Pereira, for whom he felt a special affinity as a free thinker in a
remarkably hostile environment (Guardia 1889: 270-291,
382-407, 607-634). He tried to present him as a victim of
the Inquisition in Spain: Pereira's unquestionable materialism
was soon persecuted, and his works almost disappeared. But, in spite
of everything, an heroic Pereira was able to exercise a scientific
methodology which helped him to overcome all the prejudices
accumulated over the long history of the scholastic school. From this
perspective, Guardia held that the third part of the
*Antoniana* devoted, as we have seen, to the immortality of the
soul, was only a subterfuge to "keep up appearances". For
him the central thesis of the book is the animal mechanism, where it
is necessary to place Pereira's great originality. With regard
to the "Cartesian question" Guardia emphasized that
neither Descartes nor the Cartesians wanted to recognize how much
their philosophy owed to this Spanish doctor. This debate on the
interpretation and the meaning of Pereira's thinking somehow
determined his recovery among the small number of Spanish scholars who
have focused their attention on the figure of Gomez Pereira
during the twentieth century (Gonzalez Vila 1977: 120 ff.).