German Paths to Experience
Matteo
Favaretti Camposampiero·
Ca’ Foscari University of
Venice, Italy
Review
of: Karin de Boer and Tinca Prunea-Bretonnet (eds.), The Experiential Turn in Eighteenth-Century German Philosophy, New
York and London, Routledge, 2021, xii+309 pp. ISBN: 978-1-138-60683-8.
As its title
clearly announces, the overall aim of this collection of studies is to present,
document, and defend the idea that, in the eighteenth century, German
philosophy underwent an experiential turn. The lexical choice of ‘experiential’
instead of perhaps more usual terms like ‘empirical’ or ‘experimental’ is not
difficult to explain. Describing a philosophical turn as ‘empirical’ would have
easily evoked the standard rationalism/empiricism distinction, which the
Editors explicitly reject as “worn out” (1), insofar as several of its
presuppositions and implications have been seriously undermined by recent
scholarship. As for ‘experimental’, though increasingly adopted in early modern
studies precisely to replace the relatively anachronistic category of
‘empiricism’, using this adjective would have put the greatest emphasis on just
one side of the issue, namely the success of experimentation within the natural
sciences and the attempts to apply similar practices to areas of strictly
philosophical investigation as well. ‘Experiential’, by contrast, aims to
express the philosophical significance acquired by experience in the widest
sense of the word. Although this may seem commonplace if referred to other time
periods or geocultural areas like the British seventeenth century or the French
Enlightenment, it is by no means trivial if referred to eighteenth-century
German philosophy, which a long historiographical tradition depicted as an age
dominated by dogmatic, intellectualist thinkers who loved speculation and
despised brute facts.
Challenging
another widespread prejudice, the book makes a case for the original and
autonomous character of this German experiential trend – first, by dismantling
the idea that any German philosophical interest in experience was imported from
abroad. Although some foreign champions of experience-based philosophy like
Locke had a powerful and longstanding impact on the German Enlightenment,
German authors could also draw on native sources. Lutheranism and especially
the Pietist movement certainly contributed to shaping a positive image of
experience, which was to attract those who, like the Thomasians, sought an
alternative to the Wolffian paradigm (4). In “The Thomasian Context: Crusius on
Experience”, Stefan Heßbrüggen-Walter reconstructs the doctrinal evolution
within the so-called Thomasius school, which made the transition from a
sensation-based account of experience (shared by Andreas Rüdiger, Johann Jacob
Syrbius, and Johann Franz Budde) to Adolph Friedrich Hoffmann and Christian
August Crusius’s propositional view. The main opponent of this trend, Wolff,
was himself strongly influenced by German sources in his assessment of the
epistemic function of experience. In “Before
and Beyond Leibniz: Tschirnhaus and Wolff on Experience and Method”,
Corey W. Dyck argues that Tschirnhaus’s “experimental Cartesianism” (18) had a
decisive impact on the young Wolff, in that it prompted his adoption of the
geometrical method and his consequent ascription of a pivotal role to empirical
evidence in the procedures of both discovery and justification. According to
Dyck, the Tschirnhausian imprint of Wolff’s early philosophical project not
only lasted throughout Wolff’s intellectual trajectory, even after his contact
with Leibniz’s thought, but oriented his very reception of Leibnizian
epistemology. (A question that might cross one’s mind, however, is why not
turning the tables and claiming that the Tschirnhausian elements that Wolff
still retained in his post-Leibnizian works were precisely those that proved
compatible with Leibniz’s doctrines, since the incompatible ones were
immediately discarded.)
A further typical
feature that this book ascribes to the German experiential turn is (somewhat
paradoxically) the theoretical effort to analyze the very concept of
experience. German philosophers did not content themselves with the
commonsensical, pre-theoretical notion of experience (3) but sought to
characterize its nature and determine its functional role in cognitive
processes. As Heßbrüggen-Walter notes (82), this approach spread only after the
publication of Wolff’s German Logic
(1713), whose sophisticated treatment of experience made even his opponents
feel bound to specify their own understanding of this concept.
The third (and
perhaps most important) distinctive trait of the German rediscovery of
experience is its connection with metaphysical issues. In this respect, too,
Wolff laid much of the groundwork for most subsequent debates, maintaining for
instance that “even in abstract disciplines like first philosophy [i.e., ontology], the fundamental concepts must be
derived from experience, which founds historical knowledge” (Wolff 1728, §12).
In what follows, I will mainly focus on issues and chapters directly related to
Wolffianism.
Christian Leduc’s
chapter (“The Role of Experience in Wolff’s General Cosmology”) focuses on
general cosmology, the new discipline introduced by Wolff as the part of
metaphysics which investigates the most general properties of the physical
world. Wolff provided two distinct expositions of this metaphysical doctrine of
the world: the first appeared in the fourth chapter of the German Metaphysics (1720); the second and larger one appeared some
eleven years later, in the Latin Cosmologia
generalis (1731). We should bear in mind that, in Wolff’s system, the
position of each discipline is determined by its foundational role with respect
to other disciplines. On the one hand, general cosmology is based on ontology
(the most general part of metaphysics) and specifically on the ontological
doctrine of composite beings. On the other hand, general cosmology provides the
foundations of physics. Thus, one of the functions of general cosmology is to
bridge the gap between ontology and physics, that is, between the very abstract
concept of composite being and the concepts of the concrete bodies that
populate our physical world. Leduc’s question is whether this metaphysical
approach to the physical world owes something to our empirical acquaintance
with the actual world. As highlighted by recent scholarship, Wolff was not a
purely speculative natural scientist; on the contrary, he was actively engaged
in experimental physics. But did this experimental approach to the physical
world somehow influence his general cosmology too? According to Leduc, the
answer also depends on whether we consider the cosmological chapter of the German Metaphysics or the Latin Cosmologia generalis: for “the method
Wolff employs in the German Metaphysics hinges much more on experience
than the one he employs in the Cosmologia” (38). In the eleven years
that separate these two works, Wolff’s position evolved: experience lost at
least part of the fundamental role it played in the German Metaphysics.
Although I am
largely sympathetic to this approach, which has the merit of recognizing that
there are significant differences between Wolff’s German and Latin systems, I
think that some aspects of Leduc’s reconstruction are worth discussing. To make
his point, Leduc develops two main arguments. First, he observes that Wolff’s
recourse to experience in the earlier work is “more substantial”, in that “many proofs are
established on the basis of observation and
experimentation, and in numerous sections Wolff adduces everyday experience or
scientific experiments to vindicate his views” (42). For instance, the German Metaphysics invokes empirical
evidence to establish the law of inertia. I do not find this example compelling
for two reasons. On the one hand, experience appears to provide not so much a
foundation of the law of inertia as confirmation of it. On the other hand, the
same procedure can be found in the Latin Cosmology
as well. After demonstrating the proposition that “Every body resists motion”, Wolff adds empirical confirmation of this:
“In the actual world, the same is confirmed a
posteriori” (Wolff 1731, §129). The same Latin formula (“In
mundo adspectabili idem confirmatur a posteriori”) occurs several times in
this work, which shows 1) that experience also plays a role in the Latin Cosmology, and 2) that experience is
always about the actual world alone (the mundus
adspectabilis).
This latter point
leads us to Leduc’s second argument: whereas the doctrines of the Latin Cosmology are meant to apply to every
possible world, the cosmological chapter of the German Metaphysics “is concerned with the physical world such as it
is known through actual perceptions. Wolff did not necessarily believe that the
treated cosmological principles were applicable to all possible worlds” (42–43).
One might object, however, that it is precisely in the cosmological chapter of
the German Metaphysics (see §569)
that Wolff formulates, for the first time, his doctrine of possible worlds.
Indeed, it is this doctrine that makes the cosmological chapter essential for
the final, theological chapter, since by establishing that
other worlds are possible Wolff can establish that the existence of this
world is contingent, which provides a premise for demonstrating the existence
of God. Thus, I am inclined to think that the doctrine of possible worlds was
an essential part of Wolff’s project of general cosmology from its inception.
Of course, Leduc
acknowledges that experience is not absent from the Latin Cosmology. He quotes an interesting passage from §5, in which Wolff
expresses his view on the relation between experimental cosmology and
scientific cosmology. However, my reading of this passage is slightly different
from his. In my reading, Wolff does not simply say that experimental cosmology
“improves” our knowledge (Leduc, 49); rather, he says that,
“to some extent, experimental cosmology can be cultivated before scientific
cosmology and can be combined with it” (Wolff 1731, §5). What Wolff appears to
be claiming is that, to some extent at least, it is possible to develop both
the experimental side of this discipline and its rational side in parallel, so
to speak, without having to establish the theory before conducting experiments
and collecting observations, or vice versa. I think that Wolff never changed
his mind on this possibility of the parallel development of a priori theory and a posteriori experience, which in this way can support each other.
Another example of
the German tendency to draw on experiential resources even outside the strictly
scientific or technological domain is offered by Alessandro Nannini’s chapter
on “Aesthetica Experimentalis:
Baumgarten and the Aesthetic Dimension of Experience”. Alexander Gottlieb
Baumgarten is mostly known as the founder of aesthetics and the author of a Metaphysics which Kant adopted as a
textbook in his lectures. The standard picture of Baumgarten pays little
attention to his connection with the experimental tradition issuing from the
natural sciences, thereby overlooking the fact that Baumgarten taught not only
aesthetics but also physics (59). By contrast, Nannini convincingly argues that
Baumgarten’s aesthetics – and especially what Baumgarten called the “aesthetic
art of experience” or “aesthetic empirics” (58) – should be read in the context
of early modern experimentalism. According to Nannini, Baumgarten’s linking of
aesthetics and experimentalism is paramount to his philosophical project and
could be described as a two-way or mutual foundation. On the one hand,
aesthetics provides a philosophical foundation for experimentalism. On the
other hand, aesthetics itself tends to develop into an experimental discipline.
A still open
issue, in my opinion, concerns the sources of Baumgarten’s project. Nannini’s
chapter is successful in widening the usual references so as
to include several neglected sources belonging to the experimentalist
tradition, but refrains from reconstructing the precise derivation of doctrines
and concepts. A case in point is Baumgarten’s treatment of sense deception in
his Metaphysica, which Nannini
describes as part of the aesthetic project of grounding the reliability of
sensory experience. Baumgarten maintains that sensations in themselves cannot
be false; if they deceive us, it is only because we infer wrong judgments from
true sensations. Nannini is certainly right in stressing the importance of the
idea that sense perceptions are basically innocent, for they are always
veridical. But what is the source of this idea? Is it the experimental
tradition or rather Leibniz, as Nannini seems to suggest by using the example
of the square tower that appears round when seen from some distance? How does
the Leibnizian inspiration of Baumgarten’s epistemology relate to the empirical
or experimental strand of his aesthetics?
As Nannini
observes, experience is relevant to Baumgarten’s metaphysics and aesthetics
also in the form of inner experience.
While the external senses provide information about the physical world, the
mind also has cognitive access to itself by means of the so-called inner sense.
In the German eighteenth-century context, this faculty was deemed crucial for
justifying the epistemic claims of metaphysical psychology, in that the mind’s
ability to directly experience its own states and perhaps even become
acquainted with its own nature provided an empirical, introspective basis for
psychological investigations. However widespread, this position was not
universally accepted. In “Christoph Meiners’s
Empiricist ‘Revision’ of Philosophy and Michael Hißmann’s Anti-Speculative
Materialism”, Falk Wunderlich argues for the existence of a materialist strand
within German empiricism, whose upholders were wary of internal experience and
trusted only scientifically codified forms of external experience. Hißmann, in particular, maintained “that
inner experience, obtained through introspection, is not informative about the
nature of the human mind and that philosophy should rather rely on the results
of medicine and physiology” (119). By contrast – as Udo Thiel shows in “Experience and
Inner Sense: Feder–Lossius–Kant” – other Enlightenment thinkers like Johann
Georg Heinrich Feder, Johann Christian Lossius, and the pre-critical Kant not
only considered inner sense to be a source of psychological knowledge but “were tempted to ascribe to inner sense an even more
fundamental role, namely, that of grounding experience and cognition in
general” (100). In his critical philosophy, Kant downgraded inner sense to a
merely empirical-psychological function. At the same time, however, he retained
“the idea of a fundamental or radical faculty that grounds
thought” by transferring this function to pure apperception. Concerning the
sources of these German developments, Thiel points to Locke’s idea of reflection as an inner source of
knowledge, distinct from outer sensation. In my view, this picture could be
usefully complemented by also taking into consideration the Wolffian tradition
of ascribing to inner sense a foundational role with respect to logic and
metaphysics, which I take to be the direct target of Kant’s late dismissal of
rational psychology as “merely an anthropology of the inner sense” (Kant 2000,
325; see Favaretti Camposampiero 2018).
A somewhat similar
consideration might also apply to Paola Basso’s chapter, “Lambert on Experience
and Deduction”. Investigating Lambert’s effort to complement the formal
procedures of a Wolff-inspired deductive method with a Lockean focus on simple
concepts drawn from experience, Basso highlights the originality of Lambert’s
own epistemology as merging “the Euclidean and Newtonian methods” (189) and
combining a priori and a posteriori elements in a “mixed procedure”
(192). In spite of Lambert’s criticism of the Wolffian
reliance on definitions, the “hybrid” a
priori Basso describes as the hallmark of Lambert’s method (193) could
actually be compared to Wolff’s own “weak” a priori (see Vanzo 2015). As
Basso herself acknowledges (193), Lambert’s endorsement of the method of
astronomy finds a clear precedent in Wolff’s suggestion that both philosophers
and physicians should imitate astronomers (see Favaretti Camposampiero 2016).
Furthermore, Lambert’s notion of a priori
experience – however odd it might appear at first sight – might be relevant to
reconstructing his overall approach to inner experience and sensation (see
Favaretti Camposampiero 2018).
Another dimension
of inner experience that attracted the interest of Enlightenment thinkers was
the phenomenon of dreaming. In “The Role of Reason, Experience, and Physiology
in Formey’s Essay on Dreams”, Annelie
Grosse explores this topic with reference to Jean-Henri-Samuel Formey, a member
of the Berlin Academy better known for his exposition of Wolffian philosophy.
Although dreams might seem to have little to do with experience and reason,
this chapter shows that the investigation of dreams and the effort to provide a
scientific explanation for this phenomenon were a sort of testbed for the
newborn discipline of empirical psychology. Grosse argues that the Essay on Dreams stands out from other
works by Formey in that it emphasizes the reliability rather than the flaws of
sensory experience. In her interpretation, this empiricist attitude was part of
a rhetorical strategy designed to make Wolffian ideas more palatable to the
members of the Berlin Academy. On the one hand, she highlights the Wolffian
inspiration of the Essay on Dreams,
whose “methodological procedure […] corresponds to Wolff’s account of how to
establish knowledge in general, and empirical knowledge in particular” (168).
On the other hand, she stresses the originality of Formey with respect to his
Wolffian sources. Formey sought “to integrate metaphysics and natural
philosophy” (p. 160), thus overcoming the Wolffian “separation of physiological
and metaphysical investigations of the human soul” (p. 158): for, according to
Grosse, Wolff “investigated the nervous system in his natural philosophy and
the mental faculties in his metaphysics” (p. 158). So, whereas Wolff provides
only metaphysical explanations, Formey also provides physiological
explanations, and thus approaches the phenomenon of dreaming “from a completely
different angle” (p. 171).
A limit of this
assessment is that it considers only Wolff’s account of dreams in the German Metaphysics, without paying
attention to the Latin works and especially the Psychologia rationalis, which develops a theory of dreams based on
physiological principles. According to Wolff, the state of the dreaming soul
corresponds to a certain state of the brain, for every mental process has a
corresponding physical process in the brain. Before Formey, Wolff’s Psychologia rationalis had already integrated the physiology of the nervous
system into the metaphysics of the soul. Should we then infer that, in this
perspective, Wolff’s Latin works are more empirically founded than his German
works, contrary to what was the case with general cosmology in Leduc’s chapter?
I would resist this conclusion. For why should we assume that physiological
explanations are more empirical (or evidence-based) than metaphysical
reasoning? The physiological model of the brain and nervous system that we find
in both Wolff and Formey is largely hypothetical: it derives more from
Cartesian speculative physiology than from an empirical observation of the
inner workings of the brain. Thus, I am reluctant to equate ‘physiological’
with ‘empirical’. From the Wolffian point of view, the theory of dreams that
Formey develops in his Essay belongs
to rational psychology rather than to empirical psychology.
The anti-Wolffian
faction of the Berlin Academy is mainly represented in this volume by
Pierre-Louis Moreau de Maupertuis and Jean-Bernard Merian. In “Contingency and Experience in Maupertuis’s Essay
on Cosmology”, Anne-Lise Rey argues that Maupertuis’s
hostility towards rationalism and his endorsement of experimentalism did not
prevent him from developing “a metaphysics centered on teleology” (142), which
escapes our rigid dichotomies between Newtonianism and Leibnizianism. Rey’s
reconstruction focuses, on the one hand, on
Maupertuis’s physico-theological account of the laws of nature and, on the
other hand, on his rejection of the absolute certainty of mathematics in favor
of moral certainty and probable knowledge. Like Maupertuis, Merian
sought “a ‘third’ or ‘middle path’ that combine[d] empiricist
and speculative features” by avoiding both dogmatism and radical (i.e. Humean) skepticism (Tinca Prunea-Bretonnet, “On the
Mitigated Phenomenalism of J.-B. Merian”, 203). Prunea-Bretonnet describes the
view emerging from his work on apperception as “a phenomenalist
position founded on empiricist premises” (205), while she characterizes his
overall metaphilosophical approach as a form of eclecticism.
The book’s final
section is devoted to Tetens and Kant. In “Tetens on the Nature of Experience Between Empiricism and
Rationalism”, Clinton Tolley and R.
Brian Tracz challenge the mainstream narrative that depicts Tetens as a staunch
empiricist, by highlighting some Leibnizian commitments in his account of the
origin of concepts, as well as his progressing beyond Locke and Hume’s notion
of experience. Conversely, in “The Role of Experience in Kant’s Prize
Essay”, Courtney D. Fugate addresses the vexed issue
of the early Kant’s alleged failure to depart from rationalism by arguing that
the experience-based method he prescribed for metaphysics in his Inquiry Concerning the Distinctness of the
Principles of Natural Theology and Morality in fact “embod[ies]
the anti-rationalist spirit of Bacon and Newton” (233). Focusing on the Inquiry and the Dreams, Karin de Boer’s chapter
(“Kant’s Inquiries into a New Touchstone for Metaphysical Truths”) investigates
Kant’s pre-critical strategies for using experience to delimit the pretensions
of metaphysics without completely dismissing the purely intellectual dimension
of knowledge. Reassessing the role which Wolff’s German Metaphysics ascribes to inner experience in establishing
metaphysical concepts and truths, de Boer argues that “Kant’s
position during the 1760s was closer to Wolff’s in this regard than appears at
first sight” (278).
This volume contains
a wealth of original, insightful analyses and remarks which will certainly
stimulate further discussions in a field of scholarship that is currently
attracting more and more attention. Anyone interested in the history of early
modern German philosophy will benefit from reading it. A general question that
remains open is: if all these German philosophers agree in reevaluating (outer
as well as inner) experience as a source of knowledge, why do they appear to be
divided into two main groups – which is what has made the standard
‘rationalists vs. empiricists’
narrative so persuasive? If they all belong to one and the same philosophical
turn, if they all “attempted to reconcile rationalist and empiricist
accounts of cognition” (6), how are we to explain their taking sides with
one or the other camp? By rejecting the standard rationalism/empiricism
distinction as worn out, do not we risk losing
sight of the strenuous oppositions that split the German eighteenth-century
philosophical scene with regard not only to specific topics but also to general
metaphilosophical issues? For instance, both the Pietists and Wolff firmly
relied on experience, yet they could find no common ground. One
reason might be that they invoked experience for different purposes, namely either
to set boundaries on reason, as with the Pietists, or to enhance its use, as
with Wolff (see Goldenbaum 2016). The experiential turn appears to have involved
different, divergent, or even mutually incompatible paths.
Bibliography
Favaretti
Camposampiero, M. (2018), “Anthropology from a Logical Point of View: The Role
of Inner Sense from Jungius to Kant”, in G. Lorini and R.B. Louden (eds.), Knowledge, Morals and Practice in Kant’s
Anthropology, Palgrave Macmillan, Cham, pp. 43–61.
Favaretti
Camposampiero, M. (2016), “Bodies of Inference: Christian Wolff’s Epistemology
of the Life Sciences and Medicine”, Perspectives
on Science, 24, pp. 361–379.
Goldenbaum, U.
(2016), “It
Is not Experience That Matters in the Battle of
Rationalism and Empiricism, or how Theology Favors Empiricism over
Rationalism”, in A. Pelletier, Leibniz’s
Experimental Philosophy, Steiner, Stuttgart, pp. 41–67.
Kant, I. (2000), Critique of the Power of Judgment,
Cambridge University Press, Cambridge.
Vanzo, A. (2015),
“Christian Wolff and Experimental Philosophy”, Oxford Studies in Early Modern Philosophy, 7, pp. 225–255.
Wolff, C. (1728),
“Discursus praeliminaris de philosophia in genere”, in Philosophia rationalis sive Logica, methodo scientifica pertractata,
Renger, Frankfurt and Leipzig, pp. 1–104.
Wolff, C. (1731), Cosmologia generalis, methodo scientifica
pertractata, Renger, Frankfurt and Leipzig.
