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Kant and the Thing in Itself

Ralph Blumenau on why things may not be what they seem to be.

Before Kant, philosophers had divided propositions into two kinds, under the technical names of ‘analytic’ and ‘synthetic’. Propositions must be either the one or the other. Analytic propositions follow up the implications of definitions. If we designate the number of asterisks in *** as ‘3’, the number in ** as ‘2’, the number in ***** as ‘5’, and the symbol for addition as ‘+’, then it must be true that 3 + 2 = 5. If we use the word ‘man’ for the male of the human species and the word ‘father’ for the male progenitor of a child, then it must be true that ‘fathers are men’. The truth of these propositions is self evident; experience will confirm it; but it could never be falsified by and is therefore independent of experience: it is prior to experience, and such propositions are accordingly called a priori.

In his Critique of Pure Reason (1781), Immanuel Kant significantly extended the range of a priori truths. He held that we bring to bear on the world not only our senses, nor only those a priori truths which unfold from definitions. The way in which our minds operate on the world is dictated by the way our minds are constituted, and this constitution is also a priori, that is, it does not derive from experience, though, like the unfolding of definitions, it will subsequently be applied to experience.

Forty years earlier, David Hume had demonstrated that we have no evidence to be certain that there is such a thing as a cause: all we can know is that very often, or even always within our finite experience, A is followed by B. Similarly, he showed that when we talk about space and time, we are merely expressing our repeated experiences of physical and temporal distance. He had then added that of course we cannot in real life do without the notions of cause, space or time; we constantly show that we have a belief in causes etc; but he insisted that they were only beliefs, and that we had no philosophical reason for knowing that they really existed.

Kant now asked himself why ‘we cannot do without’ these notions. Hume had suggested that it was because they were useful and that without them we just couldn’t live; but he was clear that the entertaining of such notions lacked philosophical rigour and was therefore a kind of intellectual laziness. Kant was sure that there was a great deal more to it than that. He held that thinking in terms of causes was not a philosophical aberration, but arises out of the very essence of the way the human mind is constituted, the essence of the way it is compelled to reason. When the mind looks at the world, it has no choice but to view it with ideas that are built into the mind. This looking Kant called Anschauungen. The German noun means quite literally ‘viewings’; and the technical translation into English, ‘intuitions’, does not in its everyday sense capture that meaning at all, although it does come from the Latin intueri, meaning to ‘look upon’. Leibniz had called these ideas ‘tools of understanding’; Kant called them Concepts and Categories, and they, too are a priori: that is to say they come before any experience and they shape the experiences we subsequently have.

Both Leibniz and Kant knew of course that these tools of understanding are not present in a baby, but in their view they are genetically programmed to develop without having to rely on experience. The baby cannot play football because its leg muscles are not developed; but they are programmed to develop naturally (if the baby is not afflicted by a disease) as it matures. In the same way, the baby is not aware of tools of understanding, but these, too, in the absence of disease, naturally develop as the baby matures. Locke had said that the mind at birth is tabula rasa – a blank slate – and that there are no innate ideas. Leibniz and Kant differed from him in claiming that such developments are innate and not the result of experience, though experience and training may speed up and above all refine the development of these tools so that we can use them more effectively.

So the world reaches us already mediated through these tools of understanding. And what follows from that is that we can have no direct knowledge of the world as it is before this mediation has happened. The world as it is before mediation Kant calls the noumenal world, or, in a memorable phrase, Das Ding an sich, a phrase which literally means “The thing in itself”, but whose sense would be more accurately caught by translating it as “the thing (or world) as it really is”(as distinct from how it appears to us). He calls the world as it appears to our senses (after mediation through our tools of understanding) the phenomenal world.

These tools of understanding, which I will be describing below, also have what he called a transcendental character. This confusing word doesn’t refer to the world beyond the world of appearances (for which Kant uses the word transcendent) but to ideas which transcend or go beyond any one person’s ideas and are shared by all human beings, not by any one self but by the transcendental self, and are therefore not merely individual constructs. The subjectivism necessarily involved in a situation where the objective nature of the noumenal world must be hidden from us is therefore a collective subjectivism. As such, it presents a kind of objectivity against which the subjectivity of an individual can be assessed. For example, in their developed state these collective Anschauungen present a system of reasoning in the context of which we can say whether an individual is using reason properly or not. At least this means that we are not condemned to solipsism. That part of Kant’s teaching which deals with the nature of the ideas which all human beings share is therefore called Transcendental Idealism.

Bertrand Russell explains Kant’s theory with an analogy, which I am extending a little here. If all people were born with blue-tinted spectacles that they could never take off, the unphilosophical person would assume that all the colours of the world have a bluish tinge. But philosophers, once they have realized that these tinted spectacles (since we all wear them, we might call them ‘transcendental spectacles’) are an irremovable part of our visual equipment, will come to understand that we cannot know what the colours of the world are really like because they can only reach us as mediated by our ‘transcendental spectacles’. The philosopher will know that he is receiving signals from outside; he will be aware that there is something ‘out there’ which is sending the signals; but he will also know that the signals he is capable of receiving depend on the nature of our receiving apparatus. The apparatus may by its very nature distort the signals and indeed miss out a whole range of them. To those signals we cannot receive we are blind, and we can have no conception of them. We might also add that the apparatus which we all have is often not even used by individuals as it should be: by not paying enough attention to his spectacle lenses a person could have allowed them to become smudged, so that for him they would produce an unreliable picture even of the phenomenal world.

But will the philosopher really know that there is something that is sending the signals? Should Kant not rather have said that he will assume the existence of an external source of the signals? Indeed, later critics will go further: if the Ding an sich is unknowable, we can have no reason for assuming that it exists at all. Some of them will therefore revert to pure Idealism: that our ideas are the only things of which we can be certain. Such critics would be unimpressed by the analogy, for example, that astrophysicists receive signals from outer space without knowing their source, or, if they do know the source, without knowing what that source is like. If the critics are pure idealists, they would say with Hume that, philosophically speaking, all we can be sure of is that we have ideas about these sources, irrespective of whether they are ‘known’ or ‘unknown’, but that we can have no grounds for thinking that there really are sources ‘out there’ which cause these ideas.

Again, to extend Russell’s analogy further, we know that the eye of a fly is so constituted that the single images we see appear to the fly as multiple images. We think that the fly’s vision of the world is inaccurate because it doesn’t correspond to our vision; but how do we know that our vision accurately pick up the signals the world sends out? In fact, we know that it doesn’t: the human eye is incapable of registering ultra-violet or infra-red colours, just as the human ear is incapable of receiving the high-pitched sounds that a bat can hear.

We might think that, because these examples relate merely to our sense impressions, science can come to our rescue and tell us that there are signals which we cannot perceive directly through our senses alone or which we perceive inaccurately. But a full-blown Kantian would have to say that science comes to our rescue only as far as the phenomenal world is concerned: we cannot know whether or not science can give us a reliable picture of the noumenal world. To understand the full significance of what Kant was saying requires us to extend the above examples of the limitations of our sensory equipment (of sight or hearing) to the limitations imposed on us by our reasoning equipment. Our reason does not read off or deduce from the signals of the nouminal world what that world is like. The way our rational equipment interprets those signals constitutes the phenomenal world. This interpretation forms our ‘knowledge’, and because knowledge is interpretation, it is not so much something we have as something we do. We shape the phenomenal world with our tools of understanding. For example, because we cannot perceive the noumenal world directly, we cannot know whether it has an order or not. Therefore such sense as we have of the universe being orderly is not imposed by the universe on us, but is imposed by us on the universe.

Kant believed that by this insight he had brought about a ‘Copernican Revolution’. Copernicus had replaced the old idea that the earth was the centre of the universe: the sun was now its centre. This radically shifted the perspective with which men looked at the world and their place in it. Kant created a similar shift of perspective, from the idea that the world as we experience it is something that is given to our mind to the notion that it is determined by our mind. In the 19th century the Germans particularly took to this conception that the world is a product of the mind (and, later, of the Will). More soberly, twentieth century scientists and philosophers reinforced the notion that we can only understand the world through the conceptual apparatus, the tools of understanding, that we have.

It is important to realize that, though the tools of understanding are not adequate to reveal to us the real nature of the Ding an sich, they are, within that limitation, extremely ‘high precision’ tools. There are the most rigorous rules for using our reasoning faculties properly. The phenomenal world on which we use them therefore of necessity conforms to these rigorous rules: it is a rational world. If we impose an ‘erroneous’ view on the world of appearances – for example, the idea that the earth is flat or that blood is made in the liver – it is because our tools of understanding have not been deployed properly. However, as long as we do impose faulty reasoning on the world of appearances, we will believe that that world conforms to our faulty reasoning; in other words we will still see the world as conforming to the rules of reason as we understand them at any given time. When subsequently our reasoning is used more precisely, our view of the world of appearances changes accordingly.

This accounts for the fact, for instance, that every European in the Middle Ages believed that the earth was the centre of the universe or that Man was created in the way the Bible. In later ages Copernicus and Darwin deployed their reasoning apparatus in such a way that they persuaded the majority of people to look at the world with tools of understanding that were more sophisticated and gave us a better understanding of the phenomenal world of appearances (though we should still remember, firstly, that even the more refined tools of understanding used by Copernicus and Darwin may not have delivered the last word on astronomy or evolution in the phenomenal world; and, secondly, that we still have no certainty about what the noumenal world is like.)

What, then, are these ‘tools of understanding’? Kant calls some of them concepts and others categories, though he sometimes refers to concepts as categories. Both have the same characteristic of imposing order on our perceptions.

There are first the concepts of Space and Time. Our minds are made in such a way that we have to order our perceptions in a spatial and temporal way; and they cannot imagine a world which has more than three dimensions or does not obey a temporal sequence. If, therefore, in the noumenal world more than three dimensions or some kind of non-sequential time did exist, we would be incapable of grasping that.

When he comes to categories, these are an elaboration of Leibniz’s ‘tools of understanding’. For Leibniz these had been the innate notions of being, substance, unity, identity, contradiction and cause. Kant divided categories into four groups, each of which he then subdivided into three further groups.
Here is Kant’s elaboration:

First we have ‘categories of quantity’: the notions of unity, plurality, and totality.

So we have, prior to experience, notions which we subsequently apply to experience, of ‘one thing’, of ‘several things’, and (more arguably?) of ‘universality’ or ‘completeness’. Then there are ‘categories of quality’: reality, negation, and limitation.

We apply to experience the a priori notions of what we consider ‘real’: we have a tool of understanding which discriminates between ‘is’ and ‘is not’; and it also applies an alternative to ‘is’ and ‘is not’, namely ‘is only in part’.

The ‘categories of relation’ are: substance and accident; cause and effect; activity and passivity.

We expect, prior to experience, to see a relationship between a basic object (say, what makes a rose different from an orchid) and variables (like the rose’s colour). One wonders, however, whether the distinction between substance and accident is really innate: surely it is not intuitive, but learnt from experience? As far as cause and effect are concerned, we have already seen above that this notion, which Hume had considered to be the result of philosophical laziness, was thought by Kant an essential part of our make-up. So, he thought, was the notion of the difference between ‘acting’ and ‘being acted upon’.

The ‘categories of modality’ are: possibility and impossibility; existence and non-existence; necessity and contingency.

When we consider a proposition about the world and decide that that proposition is impossible, our decision may be wrong; but we do not need to have learnt from experience what ‘impossibility’ is. The same goes for existence and nonexistent. The belief in the existence of fairies may be wrong, but our notion of existence is inborn. Again we may be wrong in deciding that B must always follow from A (necessity) rather than it merely happens to accompany A in this case (contingency); but in that case we have merely applied inaccurately our innate notion of the difference between necessity and contingency.

It can be seen that these categories are all essential ingredients of logic. Every logical argument aims to use these tools of understanding correctly. Formal logic, as it had been developed since the time of Aristotle, consists of rules that should help to ensure the correct handling of these tools. As we have noted above, a tool can be used accurately as well as inaccurately. The fact that, for example, we have an a priori concept of cause and effect does not mean that we always argue rationally from cause to effect. The more effectively we use our reason, the more fully comprehensible the phenomenal world will be for us. Kant, as a child of the Age of Reason, trusted implicitly and explicitly that Reason, properly handled, will give us a wholly reliable and coherent account of the phenomenal world, and an increasingly perfect understanding of the Laws of Nature which govern that phenomenal world.

This trust in Reason – that, properly used, it produces absolute and not relative truths about the sensible phenomenal world – was shared by most of Kant’s contemporaries. But the philosophes and their heirs certainly did not agree when Kant extended this certainty into the areas of morals and religion. He maintained not only that certain religious concepts are also part of our a priori mental equipment, but that our minds are so constituted that we must have a belief in God, in Free Will and in the imperishability of the Soul.

I find Kant’s view, that these religious ideas are the inescapable tools of understanding with which we have to interpret the world, truly astonishing. For a start, he must have known that there were Christians who believed in Predestination or Determinism and denied Free Will. Nor can he have been unaware that some people were atheists: Holbach’s Système de la Nature had been published eleven years before the Critique of Pure Reason. All this should have shown him that he was plainly wrong when he extended to religion the innate, a priori, inescapable characteristics of the concepts with which we reason. Our minds are clearly not so constituted that they must have these concepts of God, Free Will, and Immortality of the Soul and must therefore view the world through them.

In his two later Critiques, Kant went even further: in the Critique of Practical Reason (1788) he maintained that moral precepts, too, were a priori, categorical, absolute and invariable; and in the Critique of Judgement (1790) he looked for the same certainty in aesthetics also. But even if he hoped for too much, there is still much relevance in Kant’s insistence that we have to examine the world with the tools of understanding that we have and that, properly used, these tools give us a disciplined and coherent method with which to study the world of appearances.

© Ralph Blumenau 2001

Ralph Blumenau lives in London and teaches philosophy at the University of the Third Age.

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