Although I am greatly attracted by Idealism, I am critical of modern, i.e. epistemological Idealism. In my view, we should accept Idealism on ontological grounds, i.e. because it offers the best explanation of reality, and not primarily on epistemological grounds. As I intend to argue in a following post, epistemology alone can never provide a sufficient justification for the Idealist thesis. In particular, the master argument for modern Idealism remains vulnerable to skeptical attacks. For from the mere fact that knowledge of objects is only possible of objects within consciousness, it does not follow that all objects are within consciousness; there might still be unknown or even unknowable objects.
To this skeptical retort, modern Idealism has no satisfactory answer, precisely because it rests its case on our epistemological confinement to consciousness. If we are indeed trapped within the circle of consciousness, then – as the epistemological Idealist emphasizes – we cannot prove the existence of a reality outside of consciousness; but then neither can we disprove that existence. This is the weak spot of modern Idealism, the point at which it remains vulnerable to skeptical counter-attacks. To prepare the way for this critique of epistemological Idealism, this post explains why the Idealisms of Berkeley, Kant, and their successors took this epistemological form.
The Way of Ideas and Its skepticism
To understand why modern Idealism took this epistemological form, we have to place it in the context of its origination, namely, the Way of Ideas developed by Descartes, Locke and their followers, and the radical epistemological skepticism to which it led. As explained in a previous post on this blog, the Way of Ideas led to skepticism because it had ‘imprisoned’ the knowing subject within the “circle of consciousness”, hiding external reality behind a “veil of perception”. As the Cartesian philosopher Arnauld put it: “We have no knowledge of what is outside us except by mediation of the ideas within us.” (Arnauld 1964 : 31) Thus arose the skeptical question: If all we know directly are the ideas within our consciousness, how can we know if these ideas correspond to a reality outside our consciousness, indeed, how can we know there is an external reality at all? We cannot, after all, step outside our consciousness in order to inspect its correspondence, or lack thereof, with external reality. This threat of skepticism was sharply felt by Descartes, Locke, and their successors, some of whom – most famously Hume – went on to argue that skepticism was indeed inescapable.
It was to counter this threat of skepticism that Berkeley and Kant developed their respective versions of Idealism. As both of them pointed out, the skepticism induced by the Way of Ideas turned on the assumption of a reality external to consciousness; strike that assumption, they argued, and the threat of skepticism vanishes. If reality is ‘just’ a product of the mind itself, then surely its knowability can pose no problem for us?
|George Berkeley (1685 - 1753)|
Berkeley had designed his Idealism particularly with the intent to save common sense from skepticism. Common sense says that the objects we perceive by our senses are indeed as we perceive them: they have the colours, smells, tastes, auditory and tactile qualities we perceive in them. The Way of Ideas, however, had placed all such “secondary qualities” within consciousness, locating the real object outside the latter, as the external cause of those sensations. When we eat an apple, for example, we see its redness, taste its sweetness, feel its smooth skin, etc. But according to the Way of Ideas, all these sensations are not qualities of the apple itself; the real apple is just some material structure in space and time of which we know nothing except what physical science tells us (and even the truth of physics became doubtful after Hume’s critique of causality). For Berkeley, this skeptical doubt concerning common sense, induced by the Way of Ideas, was absurd:
“Upon the common principles of philosophers, we are not assured of the existence of things from their being perceived. And we are taught to distinguish their real nature from that which falls under our sense. Hence arises Scepticism and Paradoxes. It is not enough that we see and feel, that we taste and smell a thing. Its true nature, its absolute external entity, is still concealed.” (Berkeley 1969 : 3)
It was therefore to redeem common sense that Berkeley argued for Idealism, which in his case amounted to the thesis that sensible objects do not exist unperceived: “Their esse is percipi,” as Berkeley famously put it (1995 : §3). Perceptible objects, he argued, are nothing but bundles of sensible qualities in consciousness. Thus, through his Idealism (or “Immaterialism” has he called it), Berkeley could restore the common-sense belief that when we eat an apple, and see its redness, taste its sweetness, etc., we are eating, seeing and tasting the apple itself, not just its appearance as distinct from the real thing. The real apple, for Berkeley, is this bundle sensations; there is nothing beyond it. Berkeley made the same point by contemplating a cherry (fruit, apparently, lending itself very well for Idealist argumentation…):
“I see this cherry, I feel it, I taste it […]: it is therefore real. Take away the sensations of softness, moisture, redness, tartness, and you take away the cherry. Since it is not a being distinct from sensations; a cherry, I say, is nothing but a congeries of sensible impressions, or ideas perceived by various senses: which ideas are united into one thing (or have one name given them) by the mind; because they are observed together.” (Berkeley 1969: 117)
In his Three Dialogues between Hylas and Philonous, Berkeley makes his alter-ego Philonous (Greek for “Lover of mind”) respond as follows to the insensible matter beyond sensory experience defended by Hylas (Greek for “matter”):
“I am of a vulgar cast, simple enough to believe my senses, and leave things as I find them. To be plain, it is my opinion that the real things are those very things I see and feel, and perceive by my senses… A piece of sensible bread, for instance, would stay my stomach better than ten thousand times as much of that insensible, unintelligible, real bread you speak of… Away then with all that Skepticism, all those ridiculous philosophical doubts. What a jest is it for a philosopher to question the existence of sensible things, till he hath proved it to him from the veracity of God1; or to pretend our knowledge in this point falls short of intuition or demonstration! I might as well doubt of my own being, as of the being of those things I actually see and feel.” (Berkeley 1969 : 90-1)
As Berkeley admitted (see idem: 110), it is a bit strange to defend common sense by declaring that perceived objects exist only within the mind – a view that directly violates common sense, for which perceived objects ‘evidently’ exist outside the mind – but, according to Berkeley, it is the only way to save the reality of the sensible object within the context of the Way of Ideas. Idealism is the bitter medicine that common sense must take in order to cure it from the illness of skepticism.
|Immanuel Kant (1724 - 1804)|
For Kant, it was a different aspect of the skepticism induced by the Way of Ideas that brought him to accept Idealism. What worried him was not so much the affront to common sense as the affront to physical science presented by Hume’s skeptical attack on causality. As Kant noted in the Prolegomena, it was Hume’s attack on causality that first aroused him from his “dogmatic slumber” and stimulated the development of his “transcendental Idealism” (Kant 2001 : 5). Hume had shown, convincingly according to Kant, that our causal claims about reality are thoroughly unsupported by the sensations caused in us by external objects. We say, e.g., that fire causes smoke, but all the evidence we have is that sensations of smoke regularly follow sensations of fire. In the sensations themselves we find no reason why one should follow the other. Moreover, we cannot generalize from a finite number of past observations to universal claims: the fact that up till now sensations of smoke have followed sensations of fire does not guarantee that this will be so in the future as well (the problem of induction). As Hume put it:
“Thus not only our reason fails us in the discovery of the ultimate connection of causes and effects, but even after experience has informed us of their constant conjunction, 'tis impossible for us to satisfy ourselves by our reason, why we should extend that experience beyond those particular instances, which have fallen under our observation.” (Hume 2003 [1739-40]: 66)
Kant was deeply disturbed by Hume’s attack on causality. His respect for the physical science developed by Copernicus, Galileo and Newton was so great that he simply could not stomach Hume’s dismissal of causal laws. The stunning success of the new science, especially Newton’s discovery of the laws of motion and gravitation, meant that Hume had to be wrong. And where he went wrong, according to Kant, was in his assumption that causality, if it exists at all, must be a feature of external reality, in other words, that causal connections must be connections between real objects, independent of our consciousness. But, as Kant argued, such external objects are “nothing to us”. Objects become something for us, i.e. they become accessible to us as experienceable and knowable objects, only if they conform to our forms of cognition, and causality is one such form. Raw sensations do not yet give us experiences of objects. The sensations have to be ordered by our forms of sensory intuition (space and time) and our forms of conceptual understanding (the categories, prime among which is causality); only then do we experience a single, ordered, integrated reality consisting of interconnected objects. This, according to Kant, explains our ability to make objective causal claims: because causality is not a feature of external reality but rather a cognitive form in our mind, a form to which objects must conform in order to become experienceable and knowable.
Kant’s Idealism, then, extends only to the forms of empirical reality, not to the sensory material structured by these forms. This is why Kant calls his philosophy “transcendental Idealism”, the term “transcendental” being his technical term for what pertains to the a priori forms of consciousness: “I call all cognition transcendental that is occupied not so much with objects but rather with our a priori concepts of objects in general.” (CPR: A12) In extension, Kant speaks of the “transcendental subject” as the subject who applies the a priori forms of cognition to the sensory material.
Ultimately, the necessity of the object to conform to our forms of cognition has to do with the fundamental role Kant accords to self-consciousness in experience and knowledge. This point is often described, rightly, as the cornerstone of Kant’s Idealism. According to Kant, a process or state in my consciousness counts as an experience or belief only if I can be aware of it as my experience or my belief, thus only if it belongs to the unity of my consciousness (a consciousness that forms a unity precisely because it is mine, i.e. because all episodes and states in it are related to me as their underlying subject). For a mental episode or state to be mine, then, I must as it were be able to prefix it with the qualifier “I think…”. By prefixing “I think…” to a mental content, such as an impression of redness, thus by thinking “I think (or rather I see) redness”, I indicate that the content belongs to the unity of my consciousness. As Kant puts it:
“The I think must be able to accompany all my representations; for otherwise something would be represented in me that could not be thought at all, which is as much to say that the representation would either be impossible or else at least would be nothing for me… The thought that these representations […] all together belong to me means, accordingly, the same as that I unite them in a self-consciousness […].” (CPR: B132, B134)
According to Kant, the ultimate function of the forms of space and time and the categories of the understanding is to effectuate this unity of self-consciousness (a unity that Kant therefore calls “transcendental”, since it underlies the application of the transcendental forms of cognition). Thus only by placing all my mental episodes and states within a unified spatiotemporal network of causal relations can I recognize those episodes and states as mine, as belonging to my (self-)consciousness. The resulting integrated unity of empirical reality, then, is for Kant only a reflection or projection of the transcendental unity of self-consciousness unto the unorganized manifold of raw impressions. The unity of the object, and thereby the object as such (because there is no object without unity), is really a manifestation of the unity of the subject’s self-consciousness. In this sense, as later German Idealists would put it, the principle of subject-object identity is the central principle of Kant’s Idealism.
The Epistemological Nature of Idealism after Kant and Berkeley
Although the Idealisms of Berkeley and Kant differ greatly, they have roughly the same goal – to counter the epistemological skepticism engendered by the Way of Ideas – and use roughly the same strategy to achieve that goal, namely: argue that we can only know objects which are in or for consciousness, such that supposedly external reality falls away as irrelevant and unknowable, in which case the skeptical threat, too, falls away. The only reality left standing, then, is the reality inside consciousness. This, to repeat, is the master argument for modern Idealism – an argument either explicitly repeated or at least implicitly accepted by later German and British Idealists. They all stood on the shoulders of Berkeley and Kant, striving to improve or complete their ground-breaking but still imperfect Idealist systems (for the Germans, of course, Kant was more important, but the British Idealists drew on both Berkeley and Kant). As such, the German and British Idealists took over the epistemological agenda of Berkeley and Kant and remained within their epistemological mode of reasoning. For all of them, epistemology remained the prima philosophia, the foundational “first philosophy” that had to precede and ground all other theoretical endeavours. And even if later Absolute Idealists (such as Schelling, Hegel, Green and Bradley) went on to draw more ontological and metaphysical conclusions concerning the mind-dependence of reality, they did so ultimately because Idealist epistemology demanded it. As Frederick Beiser notes: “Although absolute idealism is indeed metaphysics, and in the very sense prohibited by Kant […], its metaphysics is necessary to solve the outstanding problem of Kant’s philosophy according to its own guiding principle.” (Beiser 2002: 369)
1. An obvious reference to Descartes’ appeal to God as the guarantor of the veracity of our perceptions, PS.
-Arnauld, A. (1964 ), The Art of Thinking. Indianapolis: Bobbs-Merrill.
-Beiser, F. (2002), German Idealism: The Struggle against Subjectivism, 1781-1801. Cambridge, Massachusetts: Harvard University Press.
-Berkeley, G. (1995 ), A Treatise Concerning the Principles of Human Knowledge. Indianapolis: Hackett Publishing.
-Berkeley, G. (1969 ), Three Dialogues Between Hylas and Philonous. Chicago: Open Court.
-Kant, I (1998 [1781-87]), Critique of Pure Reason. Cambridge: Cambridge University Press.
-Kant, I. (2001 ), Prolegomena To Any Future Metaphysics. Indianapolis: Hackett Publishing.