The Multiple Aspects of the Given—Ontological Remarks on Ernst Mach’s Empiricism

Abstract

Philosophers often rely on sciences of their own time. This is especially true for scientists writing philosophical works. In the case of Ernst Mach, the scientific references are mainly to physics, physiology, evolutionary biology and—in a somewhat different manner—the new discipline of psychology. Like so many authors in the late 19th century, Mach had extreme confidence in the methods of the natural sciences. However, this trait, often called scientism or positivism, can easily be used in polemical accounts that obscure other aspects of Mach’s thought. Mach is well-known for both his analysis of sensations and his evolutionary conception of perception and knowledge. The tension between the ambition to clarify the empirical basis of perception on the one hand and the focus on the natural origins of human perception on the other hand is, however, considerable. A comparison of these two perspectives can contribute to an ontological understanding of experience that sheds new light on the much-discussed topic of sense data and at the same time clarifies the difference between experience and observation and the role of experimental science in this context. In some respects, Mach seems closer to William James than to his followers in the Vienna circle. The accusation of idealism made by Lenin in his influential critique of positivism overlooks the implications of this naturalist approach but offers the occasion to dwell on the ontological implications of something that can be called natural historicity. Comparisons with Aristotle, Bacon, Descartes and Kant situate the empiricist theory of perception.

1. Historical Background: Philosophy, Science and Metaphysics

The European tradition of the 19th century is both close and distant to us. The first half of the century is marked by a shift from quite naturalist tendencies in France and Great Britain to a philosophy marked by German systematic thought in the aftermath of Kant, with Fichte, Hegel and Schelling as the most well-known representatives. Through his idealist radicalization of subjectivity, Hegel became an important reference from Great Britain to Russia. The materialist declinations of Hegelianism showed that the idealist approach through its stress on historicity had a political potential that transcended Hegel’s own idea of reason in history. However, the philosophical background of all these currents remained based on an all-encompassing interpretation of reality, which was quite different from the piecemeal approach of natural sciences. Those thinkers who preferred a close relationship to the methodology of the new sciences gave labels such as ‘speculative’ and ‘metaphysical’ the sense of something hyperbolically conceptual or simply unscientific. The second half of the 19th century is then predominantly marked by antimetaphysical currents. One of them has often been called positivist, a name referring to modern scientific knowledge that, through its “positive” affirmations about the sensual reality, was seen as different from logically proceeding “negative” thought, which rather excels in excluding through distinctions. The notion of positivism stems from Auguste Comte, who, in his Cours de philosophie positive, already in 1830–1842 defended a markedly scientific world view that covered not only the scientific domain but also society as a whole. The school of Comte had, however, a quite specific character, which renders it difficult to take it as a direct predecessor of positivist currents such as logical empiricism. There are, especially in the later philosophy of Comte, traits that stress the meliorist role of philosophy and combine scientism with a peculiar cult of humanity.

For Ernst Mach, closer to the scepticism of Hume as he is, the scientism of Comte is too reductive in its pronounced physicalism.1 Even if Mach is not a positivist in this sense, he has a role in the further development of the positivist tradition. As the Verein Ernst Mach with influential members such as Schlick, Carnap, Feigl, Hempel and Neurath shows, Mach is an important forerunner of the Vienna cercle. However, it is not evident that he should be classified as a logical empiricist. In some respects, he seems closer to the empiricist pragmatism of William James.2 Undeniable is that much of Mach’s work is focused on various aspects of experience, which, for him, are manifested in several mental functions but also in the epistemologically important physiological functions of the sensual faculty and in the physical aspects insofar as experience is not only an innercorporeal process.

Mach is critical towards the mentalist distinction between the subject (understood as consciousness) and its objects, and he prefers to speak of the internal in terms of personal embodiment, whereas the external world is simply what lies outside the own body. In this way, he evinces not only the idea of a subjective consciousness as epistemic anchor but also its Kantian corollary, the thing in itself. There is thus a strong phenomenalist tendency in Mach. One question in the following will be to decide whether he is able to uphold this phenomenalist antimetaphysical stance and what his theory of perception ultimately means for the distinction between subject and object. A parallel reading of the two works Analyse der Empfindungen and Erkenntnis und Irrtum [3] suggests some interesting possibilities to develop Mach’s thought in a direction that seems to differ from later logical empiricism.

One question concerns Mach’s rejection of the Cartesian distinction between the two substances res extensa and res cogitans, a dualism that he—in a quite Spinozistic way—seeks to replace with a theory of different aspects of one and the same reality.3 The stance is neither reductionist nor parallelist but is instead characterized by a strong emphasis on the multiple appearances of things. One could call this a perspectivist monism. This raises some questions about the ontological instance having such differing perspectives if it is not a Cartesian cogito or a Kantian ‘Ich denke’. Mach explicitly tells us that the subject only stands for a relative stability of experience and even suggests that the ‘I think’ could be replaced with ‘it thinks’ (es denkt).4 One could argue that subjectivity is still presupposed in Mach’s perspectivism, as a point of view seems to need a being capable of viewing in a certain way. This kind of subject would, however, differ from a subject with an object as its corollary. Instead of an object, there is a world that shows a multitude of aspects, not only to scientific observers but to everyone. Which role does reality play in such an empiricist theory?

2. Is Mach an Idealist? Lenin’s Critique

A famous critique of Ernst Mach is found in Lenin’s Materialism and Empirio-Criticism with the subtitle Critical Comments on a Reactionary Philosophy. ([5]) Even if it is quite difficult to understand how the label ‘reactionary’ could be attributed to Mach, a reading of Lenin’s influential book is interesting for several reasons. It clarifies how many Marxists later came to understand ‘positivism’ in the ideological constellation that dominated so much of the debate during the 20th century. Some striking similarities between Lenin’s arguments and similar views in the so-called “new realism” of today can also be mentioned (cf. Note 8 below) because they shed light on the core question of experience. Similarly, the approach allows the reader to see how Lenin’s political concept of materialism was established in opposition to mainly epistemological views but at the same time heavily relied on scientism—which is somewhat astonishing for somebody stressing the importance of history.5 Precisely this scientistic tendency is interesting in the present context, dealing with positivism and aiming at showing the somewhat odd position of Mach inside this movement. Additionally, Lenin’s very general critic of “reactionary idealism” offers an occasion to differentiate in order to better understand the philosophical project of Ernst Mach, which should be classified as naturalist rather than idealist. Mach had Marxist followers in Russia (Bogdanov, Valentinov, Bazarov, Chernov, Bobchinsky and others) who wanted to interpret materialism in the light of the naturalism of Mach, something that raised Lenin’s strong opposition—not least because of his own tendency to regard materialism in radical opposition to all kinds of empiricism, which he considered essentially idealist.6 Lenin suggests that Mach would adhere to the view of Karl Pearson (to whom Analyse der Empfindungen is dedicated), i.e., that “real things” are “sense-impressions” and that “any recognition of things outside the boundaries of sense-impressions” would be “metaphysics”. ([5], p.52)

And, indeed, Mach expresses similar views: “For us matter is not what is primarily given. Rather, what is primarily given are the elements (which in a certain familiar relation are designated as sensations) /.../.” ([1], p.45) For Lenin, the word ‘element’ only blurs the question as it remains linked to sensations.7 Against this, the materialist position according to Lenin, “in full agreement with natural science, takes matter as primary and regards consciousness, thought, sensation as secondary”.8

Lenin views Berkeley as the model for all later forms of idealism and thereby understands ideas as inner representations.9 There is no discussion of older conceptions like those that take ideas to be real models (Plato’s paradeigmata) for the sensual world. Lenin’s adversaries are modern philosophers from Berkeley over Kant and Fichte to Mach. When Lenin projects the Berkeleyan credo on later currents, he quotes the first part of the famous dictum esse est percipi aut percipere but dismisses “aut percipere”, i.e., the activity of perceiving. This focus on the perceptual contents, the percipi, leaves out the process of experience and thus neglects something that was extremely important for Ernst Mach, who regarded experience precisely as a natural process evolving through error and adaptation.10

Concerning the percipi, there seems to be a strange misunderstanding in Lenin, who interprets Mach’s critique of the early modern idea of a reduplication of the external world in perceptual experience as an interiorisation that ultimately leads to solipsism. This is odd. Insofar as Mach speaks of perceptual contents, he stresses that they directly manifest what is perceived without any ideal intermediaries.11 Lenin seems to defend a more dualist conception, where there is an external material world on the one hand and the perceptual reflections of this world on the other hand (even if he also adds that the perceptual reflections are carried by a material substrate, the brain and the corresponding neurological system). He somehow retains the distinction between subject and object, while attributing a material status to both of them. By ‘matter’, he understands precisely the “corporeal substance” that Berkeley (in the name of something similar to what Mach later called Denkökonomie) regarded as a purely metaphysical construction because it is not necessary in describing the phenomena. Lenin stresses “accidents or qualities without the mind”, the mind then mostly understood as the human mind (and sometimes as the perceptual faculty also of other living beings, other animals). Materialism thus has its tenor in maintaining that there is a (material) reality independent of any perceptual activity.

There are several reasons for this stance, one of them being Lenin’s stress on the non-fideist (non-religious) worldview, which he believed modern science represented. This is sometimes linked to his quite antiphilosophical defense of naive realism, as if the assumption of an independent reality would need the suppression of philosophical interrogation. “The ‘naïve realism’ of any healthy person who has not been an inmate of a lunatic asylum or a pupil of the idealist philosophers consists in the view that things, the environment, the world, exist independently of our sensation, of our consciousness, of our self and of man in general”.12 Or even more bluntly: “Materialism deliberately makes the ‘naïve’ belief of mankind the foundation of its theory of knowledge.” ([10], pp. 69–70) Lenin’s notion of matter is ambiguous. It sometimes relies on modern science and sometimes has the common-sense connotation of that which is real independently of us. Understood in the latter way, ‘matter’ seems to be another word for reality. The point is then only that reality exists. A completely different question is to decide what reality is, when it exists. The materialist answer is matter, but in order to tell what matter is, Lenin needs some kind of determination of this material substance. This brings him to the conception of matter as the object of modern natural science. It seems quite difficult to combine the two views on matter—i.e., the ordinary experience assumption of material reality on the one hand and scientific conceptions of matter on the other hand—as modern science is quite far away from what figures in ordinary experience. Physics and chemistry offer particularly clear examples of such a distance to our familiar world. The highly mathematical version of these sciences is no plausible ally of common views of reality.

If we accept the materialist assumption that reality is fundamentally material, what can we then know about this reality, and how do we acquire this knowledge? Is it matter that knows, matter that knows matter, matter that knows matter without experience...? In order to say something about the supposed material reality, experience still seems to be needed. From an epistemological point of view, experiential confirmation is what makes the difference between a pure assumption and something confirmed and plausible. Is the only point the materialist wants to make perhaps that experience has material objects? If that is so, can he then state something specific about these objects without experience? Or is the materialist proposition reduced to the simple statement that something exists independently of experience? If this is what matter means, the degree of material indetermination is considerable. Why should it be preferable to call independent reality ‘material’ and not—like Aristotle—simply regard it as the reality of what is. Why is ‘material’ a stronger word for independence than ‘essential’ (or ‘substantial’—for those who prefer to translate ousia with ‘substance’)? The examples Lenin gives—earth, sun, animals, plants—would rather indicate things with certain characteristics and thus something closer to the ousiai of Aristotle than to pure matter. Often it seems, however, as if ‘matter’, ‘nature’, and ‘independent reality’ would be interchangeable for Lenin. He thus loses sight of the problem Aristotle tackles, namely that of indeterminate first matter (protê hylê), which needs a form, i.e., a determination, in order to be a thing.13 Such questions are quite different from the modern ones, conceived through the conceptual couple subject/object. There is no starting point in self-consciousness (in the cogito) for Aristotle. The polemics of Lenin against Ernst Mach (and of his followers, called “Machists”) entirely depends on choosing a side in the modern constellation where the alternatives are spelled out as either a primacy of material reality or of consciousness (and correspondingly as materialism or idealism). Mach’s empiricism is, according to his revolutionary critic, an example of an only seemingly realist position. Ideas are here understood in the modern sense of inner representations, and all the arguments of Lenin concern the illusion of an ontological priority of perceptions, consciousness, the self or the subject. One could say that this is a post-Cartesian discussion that leaves the status of other conceptions of ideality open. However, in one sense, Lenin is quite close to the Platonic version of idealism—not concerning the Platonic emphasis on eternal stability where ideas are permanent models for things in the fluid sensual world, for Lenin certainly not an acceptable view—but regarding the Platonic disinterest in the sensual world, which offers some parallels to Lenin’s disqualification of sensation and perception as fundamental appearances of reality.

The polemics of Lenin can offer a perspective on Mach’s version of empiricism insofar as the latter can be seen as precisely a defense of real sensual qualities. Some aspects of Mach’s theory of sensation are in fact quite Aristotelian, but it remains true that Mach was inspired by the modern tradition, not only by Berkeley and Hume but, in a somewhat more distant way, also by Kant. One could even be tempted to understand the phenomenalist tendency in Mach in the light of the Kantian notion of phenomena—in spite of Mach’s reluctance to accept the notion of things in themselves ([1], p.5) and in spite of his naturalist claim that the I must be regarded as a “part of nature”, a sort of natural being-in-the-world.14 It is in this context astonishing to see how Mach, who is familiar with Kant, does not profit from the Kantian theory of imagination (Einbildungskraft) as an essential function of perception.

3. Perception and Imagination: Aristotle, Descartes, and Kant

Today, we tend to understand imagination as a sort of creative phantasy. Phantasy has then lost the (traditionally also present) connotations of an identifying function in perception and is rather associated with fiction. In order to understand the philosophical importance of phantasia and its Latin equivalent imaginatio, it is important to remember its role inside the theory of perception. For Aristotle, all thinking, perceptual experience included, presupposes phantasmata, a word one can translate with representations (and in German with Vorstellungen). It is through the phantasmata that the sensually given (aistheton) and its actualisation in sensation (aisthesis) and the corresponding sensual effects (aisthemata) become determinate appearances for the perceiving human (or non-human) animal.

The central Aristotelian function of the imagination to offer representations (appearances) already in the act of perception remained present in the medieval tradition but was increasingly regarded as problematic in early modernity. This is especially apparent in Descartes, who wanted to liberate perception from the imagination with its mostly fallacious appearances. He mentions some classical examples of erroneous perceptions such as the appearing size of the sun, which has nothing to do with its real size, which only the intellect can find out. The expression he uses for the latter kind of purified experience is solo intellectu percipere, i.e., an only-intellectual way of perceiving. The famous Cartesian argument about dreams is also situated in this context of disqualifying appearances and the corresponding faculty of imagination—dreams being obvious examples of phantasy. If the empirical knowledge of the intellect cannot rely on appearances but only on the sensual input, which Descartes understands mechanistically, there remains the dualist problem par excellence: how to find the mediation between the purely mental function of intellect (manifesting the res cogitans) and the purely corporeal function of sensual mechanisms in the human body (which is, according to Descartes, a body-machine like that of the animals). An all too strong stress on the intellect risks making the corporeal world of the res extensa part of the res cogitans. The dualism would then disappear and be replaced by a cogitative monism in which the mathesis universalis decides what is real and what is not.15 This creates a considerable tension between the innate ideas, closely related to mathematics, on the one hand, and the possibility of empirical science, dependent on sensation, on the other hand. Later, this topic recurs in the quarrel between rationalists and empiricists; however, in the end, the solution of modern science seems to be not to choose between these two but instead to combine them in something one can call the rationalisation of experience in experimental science.

The empirical problem of dualism is how to find a connection between sensual experience and clear and distinct knowledge. As Descartes has a notion of intellectual contents that is radically distinct from the phantasmata of the imagination, he has great difficulties in finding representations (ideas) that would be helpful in bringing the senses and the intellect together. His odd theory of the pineal gland mediating between the thinking and the extended substance is another well-known expression of the dualist dilemma. However, 150 years later, Kant delivers a solution to these Cartesian problems, still using the principle of the cogito, but in a different way. Kant is not trying to establish new disincarnated scientific habits (a new method) but instead takes the new science for granted and asks the quite different question: ‘How is this kind of knowledge possible?’ This gives the Kantian project a certain retroactive character. There is no new scientific principle to be established, but instead the “transcendental” necessity of finding out “the conditions of possibility” of experience, knowledge and science as something already existing. In this context, Kant rehabilitates the imagination as an epistemically legitimate faculty of perception.16 Its main function is representative. It unifies (synthesises) the sensual manifold according to certain conditions a priori in the cogito (the subject), which, for Kant, is a “transcendental self” not to confound with the empirical self. The conditions a priori—the forms of intuition (time and space) and the categories (of the four groups quantity, quality, relation and modality)—are subjective a priori not because they temporally precede the acts of experience but because they, through a “transcendental deduction” (so to say, afterwards), can be shown to be necessary preconditions.

Kant transposes the Aristotelian scheme of form and matter from the domain of things to subjective experience, matter then being the purely receptive data of sensual experience, offering the material for the two forms of intuition space and time, thus acquiring a primary determination, which is additionally constituted by the categorial forms of the intellect, quantity, quality, relation and modality. Responsible for this constitutive act in Kant is, however, a transcendental I that is precisely not “a part of nature” but, as already said, something we, through deduction, can determine as a condition of possibility of knowledge when we already presuppose that such knowledge exists.17 The transcendental constitution of objects in experience is, however, for Kant, somehow connected with the things in themselves,18 even if nothing can be known, as such, of these things. They have an influence on sensual experience because sensual receptivity is precisely receptive and not spontaneous.19

For Kant, the presupposition of a basic, purely receptive sensual multitude has as its corollary an active (spontaneous) subject that accords determinate order in experience. Appearing objects become dependent on a constitutive act, a Konstitutionsleistung. In Kant, the assumption is that the sensual material of the receptive capacity (Anschauung) is multiple and thus needs the spontaneous synthesizing activity of the subject in order to appear as something unified and determinate. Several other thinkers have taken the same path, not only Kantian philosophers but also empiricist defenders of sense data and phenomenological thinkers that accept the Husserlian notion of hyletic data.20 How should we situate Mach in this context? His notion of Empfindung seems to suggest a theory of sense data.

4. Mach: Experience without Kantian Constitutive Acts

Mach remains quite silent about the role of imagination in perception. Regarding the representations (Vorstellungen), he states that “The representations thus have to replace the sensations insofar these are incomplete and further develop the processes which originally were only conditioned by the sensations.” He stresses the difference between sensation and imagination and suggests that there is even a constant tension between sensation and potentially quite fallacious imagination.21 It is almost as if pure phantasy would be the model for his concept of imagination—a view contrary to both Kant and Husserl.22 Is this because he wants to evince the idea of constitutive acts which necessarily involves the representative function of imagination? If imagination is allowed as a representative function that, from the beginning, interacts with sensation, it is less evident that we can speak of sensation as the empirical base of knowledge and science. This latter assumption is, however, central to Mach, who states that “Matter is for us not the first given. Rather is this the elements (which in a certain familiar respect are called sensations).”23

Mach thus tends to regard imagination as something accessory that can have an important role to play in our mental life, often very close to phantasy, but is not as such an aspect of perception. The sensation (Empfindung) is regarded as an element (Element) which is not only psychical but physical and psychical at the same time, thus offering an experiential foundation in reality. Another reason for Mach’s reluctance to develop a theory of perceptual imagination is certainly linked to his biological perspective on the perceiving organism, something that is a central topic especially in Erkenntnis und Irrtum.

Perception is then more a matter of adaptation than of constitution in the Kantian sense. For Mach, there is no transcendental subject, but instead an organism (“ein Stück Natur”) that perceives its surroundings in different ways.24 One can notice that Mach is quite close here to topics in the philosophy of life (Lebensphilosophie)—even if this relationship remains implicit—and quite far from later logical empiricism. In Der logische Aufbau der Welt, Carnap accords an important role precisely to the idea of constitution (Konstitution). [15] Many issues in Mach are also related to topics in William James, another philosopher inspired by natural science, especially biology, and stressing the philosophical significance of life. [16]

Concerning the sensually given, it is, however, in this context interesting to notice that Mach also treats issues of what later became gestalt psychology. ([1], p. 87ff and especially chapter X) The philosophical importance of the gestalt precisely concerns the presence of meaning in the sensually given. Is meaning primordial even in the sensually given, or is there, in sensation, a neutral basis that, only through a certain interpretation, acquires its meaning? The latter supposition of sense data is present among several thinkers that we would regard as logical empiricists but has been widely contested. Mach’s proximity to gestalt theory seems to indicate a more subtle position, where the meaningful whole (the gestalt) is as such a given. In this respect, the elements of Mach could be meaningful without presupposing a representing constitutive act.

5. Sense Datum and Sense Data

Concerning sense data, the first thing to notice is that dare means give and datum thus the given. Often the term was used in plural and the given then understood as the multitude of sense data. How is the plurality of sense data to be understood? How can something differ without having a determinate character?25 A short development of this topic as such can here be of interest.

If the given is a gestalt, it already possesses unity in its givenness. It is more like a datum and the corresponding philosophical question is not one of synthesis but of presence. Somehow, a content is here involved, not only die Empfindung but das Empfundene. Such an immediate gestalt is rather a stimulus and not a meaning accorded by the synthetic act of a constituting subject. If this is Mach’s approach, it would differ from the phenomenological one. The processual conception of psycho-physical reality would then offer a complementary view that is less committed to the Kantian and even Cartesian presuppositions of Husserl’s version of transcendental philosophy. Instead of the constitution of intentional objects through the representation of data, there are already preformed sensual stimuli that evoke sensations. Such a content is rather a cause. The question is then not how a determinate form is constituted in a subjective act but how a “permanent possibility of sensation” (J. S. Mill) becomes actual. This actual givenness has the character of immediate presence. Ancient references do not play any significant role in Mach, but an Aristotelian frame can be helpful here. The difference between Element and Empfindung would then be that the element is a real possibility of experience, whereas sensation is the actualisation of this possibility. The element would then be much like a sensual stimulus.

How should we then understand the relationship between potential sensual stimuli, actual sensation and appearing content in the frame of a naturalist process theory? Biological interest certainly plays a role when stimuli evoke sensations, and it seems that the evocational capacity stems not from things in themselves, and not from interests alone, but from the specific constellation where things and interests interact. This does not happen on a tabula rasa, but inside a process whose continuity depends on a mnemic function—quite similar to what Mach occasionally called innate association.26 The person experiencing something can react in different situations, not only because there is biological interest involved but because this interest is manifest in contents carried by previous natural history. Contents would then be manifestations of a kind of natural historicity in experience and not of a Konstitutionsleistung. ([1], pp. 141, also 41, 49, 149, 151, 184) If this is so on the basic biological level, which is operative in the human organism, it has repercussions on other levels, too.

Elementary meaningful wholes (elements) that can become actual when given in present sensation offer the base for further elaboration, in a rudimentary way through vitally important association, then in all kinds of experience and in quite precise ways when experience becomes a search for knowledge, using conceptual means to elaborate the sensually given. Even in experimental experience, where the researcher takes the initiative, there remains a dependence on the primary givenness of the elements in actual sensation.

6. Research as Work

What does this imply concerning the kind of experience that is so characteristic of modern scientific research?27 Experiments represent a particular kind of experience where not only are the questions highly specific, but even the experimental situation is often constructed.28 In an experiment, objects are observed without the researcher being exposed to these same objects (let us say the virologist to the virus). From an ordinary and a historical point of view, experience involves much more and means precisely being exposed to and passing through something—even if this can of course at the same time be observed. Experimental science is different, conducting its experiments with observation as its core element—a praxis that can offer quite useful results. The researcher is a kind of worker and the matter he is working on offers its instrumentally relevant characteristics, sometimes even a material that can later be used in different applications. When this model of experience becomes dominant and evokes similar all-encompassing worldviews, reality itself appears increasingly as matter in the sense of a possible material for different explanatory and technical activities.

Which is the relationship between the experiential and experimental29 reality, and what can it say about the role of work in the modern conception of experience and science? Mach’s empiricism is partly about the kind of experience that has experimental science as its paradigmatic form but does not necessarily imply that experience would be only experimental.

7. Exposition and Observation

One could understand observation as a sort of taming of stimuli through a particular scrutiny in which the interested perception is kept distanciated through a stabilizing effort. Observation in this sense is contrary to exposition. All experience involves both observation and exposition, but allowing for deviations in both directions. Complete exposition would be when no variation of contents is brought into play, but the person is only exposed to influence. The other extreme is a completely detached experience, where the person only observes with the focus on various, strictly selected contents without being concerned by the things observed. This second possibility is cultivated through an objectifying mentality that has found particularly clear expressions in modern science.30 It is the strategy of the external “archimedic point” (Descartes) of observation that can have its clear and distinct ideas precisely because it does not belong to its object of study. This view is contrary to the Aristotelian conception, stressing the inherence in reality as the condition of experience, knowledge and wisdom.

If Descartes defended a rationalist philosophy, there is in the same period also the important work of Francis Bacon, he too a major critic of Aristotle. Bacon was not only an empiricist but also elaborated a conception of experience as experiment, which would later gain extreme importance in modern experimental science.31 In this case, it is not only observation that matters, but the active contribution to the experiential situation through quite definite mechanisms of control. If these mechanisms are constructed in order to give experience a particular concrete limitation that corresponds to certain research interests, experience becomes something quite different from empeiria in its original sense of confrontation with otherness. The transforming potential of experience is reduced and replaced by a more limited capacity of correction inside the specific questions that correspond to the goals of the research orientation. This is useful for advancing towards such goals but can create a problem insofar as the actively observing attitude through its twofold anthropomorphism (the anthropomorphic character of human perception as such and of the constructed experimental situation) tends to reduce the exposition of the observer to otherness.32

8. Inevitable Anthropomorphism and Its Accentuation in Experimental Science

Does man inhere in reality, or has he rather the initiative in dealing with nature? If we construct our world out of aspects that we have discovered through own initiatives, it is highly probable that the corresponding world reflects the interests related to these initiatives. Experimental science is a late confirmation of such an orientation—an expression of instrumental reason that can be understood as a highly anthropomorphic version of teleology. The world shows itself in relation to our ends. In the corresponding epistemology, there is no particular stress on a really independent reality.

Early positivism was a current of thought that precisely stressed such initiatives—the savoir pour prévoir pour pouvoir of Auguste Comte. The contrary is the case if we stress inherence in reality as the primordial fact. The human being is then more responsive than having the initiative. It seems that Ernst Mach represents an intermediate position, on the one hand, heavily relying on observation and clarifying what observation is all about, and on the other hand, defending a naturalist epistemology (and psychology) that could rather be seen as a theory of inherence ([3], pp. 25–26).

In this context, Erkenntnis und Irrtum is particularly interesting as experience is here given a biological interpretation that emphasizes the importance of error and the corresponding exposition to something that runs against our expectations—and this not only in experimental science. It is as if the life process as such is what transcends human ambitions and, thus, can at the same time modify them. Is Mach here in some respects a forerunner of the evolutionary epistemology of Konrad Lorenz? [22] In this case, his “positivism” is already quite different from the “two dogmas” of logical empiricism (verificationism and the distinction between the analytic and the synthetic), famously criticized by Quine. [23] It is evident that Mach is rather sceptical about a purely analytical dimension a priori. His heavily modified “Kantianism” not only disposes of the Ding an sich but also of the Cartesian traits of Kant’s transcendental philosophy, i.e., the subject completely detached from the world it is studying and thus offering an instance a priori. Nor does Mach adhere to a more Aristotelian idea of experience and knowledge as immanent functions of reality.33 The obstacle is here that Aristotle presupposes a primacy of the real and understands human experience only as a response to this ontologically fundamental dimension, may it be sensual or noetic—a position that, for Mach, would be metaphysical. It is almost as if Mach would accept the modern subjectivation of hylemorphism but refute dualism.

Mach sometimes emphasizes that his writings are not meant to present a philosophy. The remark seems exaggerated as he strongly defends a certain empiricism, one could even say a radical empiricism in the sense of William James, who is close to Mach not only through his empiricism but also through a certain pragmatism. Both authors also share the idea of a direct continuity between the natural aspects of experience and scientific knowledge.34 Mach’s stress on error as an epistemic function suggests similarities with Popper’s negative criterion of fallibility. All of this distinguishes Mach from those logical empiricists who suffered from a one-sided idea of verification, expressed in different ways, but having in common the view that there would be a possibility to underpin propositions with something sensually given. Mach would rather regard possible truth as something appearing when experience is further developed, also here reminding of William James, who famously claimed that truth is a word like health, wealth and strength.35

Like so many other thinkers in the second half of the 19th century, especially those influenced by the recent developments in natural sciences, Ernst Mach continuously asserts his antimetaphysical stance. It is indeed plausible to claim that Mach’s philosophical reflections are closely related to his research in physics, with biology and physiology as other relevant disciplines, even if he also argues inside a more general philosophical setting. Several questions arise. Does this specific perspective indicate that Mach has freed himself from metaphysical presuppositions—or does it only mean that there is an entire philosophical domain that remains outside his approach? The bracketing of metaphysical questions does not necessarily emancipate from metaphysical presuppositions. From Nietzsche onwards, a lot has been written about the implicit metaphysics of modern natural science in general and of the accompanying scientistic ideology in particular, showing its indebtedness to the Western metaphysical tradition. The scientific outlook of Mach’s works would in such a case rather confirm the metaphysical character. This would, however, leave the possibility open that Mach still refrains from metaphysical claims. In other words: such presuppositions would in this case not constitute his main topic. This seems indeed to be the case, but with some exceptions.

Mach belongs to those empiricists who regard the notion of a material substance as something highly problematic, especially if it is assumed that the ultimate nature of reality would be material. This sounds quite Aristotelian, but Mach’s references are rather Berkeley and Hume. All our knowledge of reality has experience as its foundation, and if there is something existing independently of experience, it certainly is not a matter with determinate properties.

9. Our Access to Reality

The question about a specific philosophy of Mach, i.e., a theory that is not only subservient to his scientific research, is difficult. Several remarks concerning classical philosophical problems and thinkers (Berkeley, Hume, Kant, etc.) suggest a general philosophical interest and not only an interest in those aspects of philosophy that are relevant to research in natural sciences—even if Mach, when he deals with genuinely philosophical questions, does this in a particular way that is guided by his scientific interest. This offers at least two possibilities for the interpreter. He can regard the presented points of view as useful clarifications of research in certain scientific domains—or he can focus on the philosophical elucidation of the epistemological and ontological status of experience in general.

From the latter point of view, science has a natural setting and antecedent history that manifests our quest for orientation or, in the words of Mach: “The biological function of science is to offer the most complete orientation possible to the human individual in possession of all his senses.”36 In order to orient oneself, various points of reference are necessary, and science tries to offer such marks in the most “complete” manner. This is precisely the foundational role of sensual elements, which are accordingly “the most elementary building pieces of the physical (and also of the psychic) world.”37 The role of physical concepts is auxiliary in the sense of being instruments for dealing with sensual experience, ([1], pp. 257, 258, 267) while also respecting the principle of economy of thought (Denkökonomie) and thus avoiding unfounded (metaphysical) exaggerations.

This also shows how Mach could defend his empiricism against the accusation of an idealistic refusal of reality. It is through its natural prehistory that the sensual faculty remains rooted in reality. It is inevitable that human experience springs forth from the natural evolution that has created the human being. Anthropomorphism as such is thus not a problem. It is completely natural that the experience of human beings is marked by the fact that they are human. If the conclusions of this experience are universalized, the risk is, however, that anthropomorphism becomes anthropocentrism. This is ontologically unsatisfying but can still be instrumentally interesting. Posed in this way, the question of instrumental reason can be articulated as a goal-related acceptance of anthropocentrism. The question is then not if instrumental science gives a true description of reality but rather how anthropomorphic the object sphere of modern experimental science must be in order to qualify for research. However, when this object sphere is regarded as the reality in itself, there is a case of pure anthropocentrism. Some physicists were quite aware of this problem. Werner Heisenberg famously said:

“In earlier epochs man saw himself opposite nature. Nature, in which dwelt all sorts of living beings, was a realm existing according to its own laws, and into which man with his way of living somehow had to fit himself. We, on the other hand, live in a world so completely transformed by man that, whether we are using the machines of our daily life, taking food prepared by machines, or striding through landscapes transformed by man, we invariably encounter structures created by man so that in a sense we meet only ourselves.”38

And more explicitly concerning physics:

“The atomic physicist has had to resign himself to the fact that his science is but a link in the infinite chain of man’s argument with nature, and that it cannot simply speak of nature ‘in itself’.”39

This is the humble insight of another physicist that in spirit is not so foreign to Mach. Could it be that modern experimental science is the logical consequence of an epistemic orientation that cultivates the voluntaristic relation to reality and thus inevitably attributes a central position to mankind in general and to a specific kind of quite active epistemic culture in particular? Experimental science would offer a particularly evident case of the anthropomorphic character of experience, where not only the experience as such is of a human kind but, through the experiments, also the experiential situations. The inevitable anthropomorphism of human experience is accentuated and useful precisely because of this.

A completely different position is that of a scientism that understands itself as an ontology and accords human experience a central position in a reality that thus becomes anthropocentric. We then have an ontological accentuation of epistemological contents instead of only the cautious assertion that knowledge must reflect the fact that it is human beings who stand for the epistemic activity.

In this sense, teleological assumptions precede the explanation of phenomena. One should thus not oppose teleological and mechanical (causal) explanations but should instead see them as different aspects or stages in the research process. Mach, however, wants to see experimental confirmation as a particularly strong evidence, “a solid experimental base”.40 At the same time, he states that the experiment is conducted willingly (willkürlich)—without taking into account how this voluntary aspect introduces a teleological element in the experimental explanation41—but he recognizes that anthropomorphism is present in all analogies and thus frequent in science. ([1], p.80)

The accentuated anthropomorphism of experimental science as such does not pose a problem, but it remains to be understood how such an anthropomorphism can offer knowledge about something real that transgresses the human perspective. This Mach tries to answer with the natural historicity of experience, its sensual base, which is still operative on all levels of experience and knowledge. I choose to call this ‘natural historicity’ and not ‘evolutionary background’ because it concerns a continuous transmission and presentation of the past that precedes specific theories such as evolutionary biology. From our perspective, it often also means that cultural historicity in the narrow sense of historical time remains marked by its natural conditions. One can, however, regret that Mach does not sufficiently develop how the cultural historicity of modern science influences its research strategies. However, this is certainly a case in which we should accept his remark that he is a physicist interested in philosophical questions and not a philosopher.

This limitation has the advantage of liberating Mach from exaggerated ontological claims and allows us to understand his theory of perception inside a specific frame, which is mainly that of modern experimental science. It is in this case not about reality as such but rather about those aspects of reality that qualify as an object sphere of this kind of science. In other words, it is an affirmation of the anthropomorphic character of this scientific approach, admitting its limitations.

No dogmatic claims about ultimate reality are intended, and Lenin’s critique is thus beside the point. If Mach’s special interest in his own discipline physics can explain the relative absence of a historical perspective, it is strange that a historical materialist with his profound interest precisely in history neglects the history and the inner logic of the sciences he uses as reference. Such an ahistorical dogmatism in fact seems to confirm the claim that Lenin wants to combat, i.e., that materialism “from beginning to end [is] the wildest metaphysics”. ([5], p. 73) The materialist form of scientism seems to be founded on the metaphysical assumption that modern science is not a cultural product but instead offers an absolutely true description of reality as it is, whereas the Machian version of scientific empiricism only expresses the limitation of a certain scientific domain. In this respect, Mach, in his own way, remains inspired by similar motives in Kant, but in a much more naturalist setting where the existence of the human organism is a self-evident starting point. This organism has a natural genesis that is reflected in the perception it is capable of. The process of experience is as such real—and we should never forget that the contents we have as pericipi always remain conditioned by this processual percipere with a long predetermining history. All experience is anchored in reality, but the particularity of the experimental experience that is so important for Mach as a physicist is that it openly assumes the actively projecting capacity of the scientific mind.

Concerning empiricism and its traditional contrary rationalism, this means that there is not only the possibility to choose a side in the quarrel. A larger concept of experience makes it possible to regard all meaningful activity as experience. This also includes the noetic experience involving reason and reasoning. Even reflection on and interpretation of the past has the transformative or confirming character that is so typical of experience. Both perceptual and noetic contents play an important role as they offer something stable, which facilitates orientation. Sometimes, these contents even have a particularly long duration, are shared by different people and different cultures, and seem to figure even among other living beings (such as water, air, earth and sun for animals). They then have an especially convincing status precisely because they seem to appear in different life forms, i.e., in different worlds that still reflect the same reality.

10. Conclusions

One question thus concerns the aspects of reality that are accessible to instrumental reason and what this can tell us about experimental science. Another much wider topic is about the relationship between experience and reality in general. If Mach’s theoretical reflections are seen as a contribution to the former question, they have the advantage of clarifying the limitations of experimental science, showing the anthropomorphic traits of its research strategy—a limitation which is, however, particularly useful and does in no way delegitimize these sciences. In this context, the accusation of “idealism” becomes irrelevant.

Concerning the ontological dimension, which is about the relationship between experience and reality in general, Mach’s position is less clear, but some claims seem to be implicit in his view on the natural background of the sensual faculty and thus also of sensations. Sensations (Empfindungen) have a close relation to something Mach calls “elements”, and he occasionally even seems to regard the terms as interchangeable. He is not completely clear on the ambiguity in the word Empfindung, which covers both act and content, but it is evident that he regards sensations as expressions of a biological background that has emerged through the past of mankind. This history is in its own way real and sedimented in our vital dispositions. In this case, there is thus a processual foundation that is much stronger than the instrumentally relevant one offered by experimental science.

It is, however, not easy to decide how one should read Mach, as mainly a physicist reflecting philosophically on natural science or as an empiricist with strong ontological claims. The proposition in this article has been to allow both perspectives.

Experience can be understood as access to reality. This does not presuppose that reality would be neither experience nor a sum of possible experiential contents. The notion of access allows a multitude of quite different forms of experience. All sentient beings are capable of experience, which is for them mainly an openness to significance. Something is significant when its absence makes a difference. An experiential community that allows for such a multitude of experience has little to do with the intersubjective community of methodologically similar researchers. As Jakob von Uexküll—another natural scientist with profound philosophical interests—has pointed out: the world familiar to us is surrounded by other worlds, more or less elusive and corresponding to quite different living beings. [28] However, nothing forces us to regard the plurality of worlds as completely disconnected from one another and, even less so, from reality as such.

When we speak of experience in the narrow sense of the so-called empirical sciences, the stress is often less on our access to reality but rather on something that is regarded precisely as the intersubjectively confirmed empirical reality of a certain research community. This innerscientific conception of reality has its meaning in allowing science to discard questions about the modes of access and its own foundation in order to better advance towards its goals. This is completely legitimate as a scientific strategy but is less so if the ambition is to understand the ontological foundations of science, which involve the larger setting of experience as such. From an ontological point of view, scientism becomes especially problematic if experience is reduced to experimental observation. However, if scientific empiricism is taken as a philosophical description of a certain epistemic approach, it can offer an understanding of what modern experimental science essentially is.

Ernst Mach offers interesting perspectives on both the specific experience in modern science and on what empirical access means in a larger setting.