summary of 2nd class

In the last post there were some of the side issues from the last class. Time for a tentative summary, since we were pretty deep in abstract-land.

1.       Structure of concepts

There is a difference between thinking of something red, and thinking of a red apple. ‘Red’ and ‘red apple’ are different, but they also seem to have something in common. How are we to explain such features of thought? Notice how common this is: we can always build more complex or more specific concepts. We can think of red apples, but also of the red apples that we bought yesterday, or the red apples that we bought yesterday from the NoName supermarket etc.

We discussed two ideas about structure: one, containment, says that complex concepts are literally made of simpler concepts – somewhat like Russian dolls; the other, inference, says that the relations between complex and simple[r] concepts are logical: if you say that you bought some red apples, you will probably accept that you bought some apples – it is not that the simpler concept – ‘apple’ – is inside the complex one – ‘red apple’. The relation between them is a stable pattern of inference. Once you accept one, you accept the other.

2.       Definitions

Let’s assume that people usually try to express what they think. They utter words that stand for whatever is in their minds. Suppose someone says she wants some coffee. She says that in English, in German, and in Romanian (this is to point out that we’re not talking about words). But, for some reason, the people around have no idea what coffee is. How could she make herself understood? And what is it that she knows – and understands – and they don’t?

One idea is that she knows something like that: ‘coffee is a drinkable liquid that contains caffeine’. When she talks about her desire for coffee, her word ‘coffee’ is a label for this definition. The definition shows the content and the structure of her coffee concept. She could try to explain what she means by making her knowledge explicit – by telling the definition to the ignorant crowd.

What is a definition? The usual way to define stuff is to give necessary and sufficient conditions. For example, the hypothetical person mentioned above would have to say something like this: ‘X is coffee if and only if X is a drinkable liquid, and X contains caffeine.’ The ‘if’ captures the fact that the conditions listed are (jointly) sufficient, while the ‘only if’ says that they are necessary. Whatever satisfies all conditions is coffee, whatever misses even one is not.

Of course the definition above does not work. Coke or tea are not coffee. But you get the picture: it was supposed for a really long time by many smart people that whatever we know and can express in language(s) can be captured by – or simply IS – a set of definitions. Concepts just are definitions. Their structure is definitional structure – conditions. One immediate problem is that when you define things, you need to stop somewhere. Where do you stop, so that your stopping point is not arbitrary?

You are free to define coffee in terms of liquid, drinkable, and caffeine if you wish. But then you must know what THOSE terms mean – that is, what concepts THEY express. What is a liquid? Suppose you say: ‘matter that flows’. What is matter then? You have an answer ready: ‘something that occupies space’. And what is space? Things get tricky soon enough.

The solution was thought to be available in the fact that we can – and must – ultimately rely on our senses. This is called empiricism in philosophy. So the basis of definitions – the primitive concepts – would be concepts of sensory impressions: patches of color, kinds of sounds or tactile stimulations etc. You can ask yourself if this can be done.

It is not necessary though to assume an empiricist line here – this is not really said in what we’ve read, so it’s worth mentioning. If one adopts the alternative to empiricism – rationalism – one can say that some primitive concepts are just innate. Our minds are never tabula rasa – we never see the world as a blur, even as infants. To come back to the example above, there might be no need to define space in terms of sensory concepts, since space might be a primitive building block of perception to begin with.

Note how this is connected with knowledge. What is the ultimate source of our knowledge? Our senses or our reason? Which if any can give us certainty? Do you know what Descartes had to say about this?

Note also how it is connected with the possibility and scope of communication. Is there a level at which we can clarify all misunderstandings that can be clarified? Is this level sensory? Can we tell what we really mean by appeal to what the senses give us?

It is, I think, in a sense true that we cannot communicate what we don’t understand quite well ourselves. But does that mean that we have definitions for what we understand? How often do we need to be VERY precise? If definitions are all or nothing (as they are in the logical sense), could  this be a realistic model of what we achieve in communication? Could it be that we have, at least within a culture, similar concepts, but different or no definitions?

3.       So why definitions?

Because we want some things from a theory of concepts and definitions seem to fulfill at least some of those desiderata (at a cost, of course). You have the list of motivations from the text – and at least we managed to say a few words last time.

We want to understand how we learn or acquire concepts. Definitions can be learned within a theory (the child supposedly develops a theory of the world – a view of how things are) by summation of conditions or features.

We want to explain why we see the world as made up of distinct objects and stuffs. We have categories and we place things into them. How do we do that? How do we classify something as coffee? Easy: check if it’s liquid, check if you can drink it, check if it has caffeine. There is another interesting question here: there is structure in our minds; but is it the structure of the world, or just an illusion? Plato wanted proper knowledge to cut nature ‘at its joints’.

We want to know why thoughts are systematic and generally consistent – why there is logic and argumentative structure in how we think about the world and ourselves. Well, definitions capture logical structure and logical relations.

Whatever the content of our concepts is, we want it to determine what the concepts are about. Say our concept of coffee is a kind of mental symbol. There must be something that connects that symbol with real, hot, nice coffee. Definitions suggest that it is a check-procedure. Reference determination – i.e. targeting what you are talking about – is done by satisfaction of the conditions specified in a definition. This is supposed to secure reference.

And so on.

Some of these ideas might seem interesting, some other might not alter you pulse at all. Try giving a thought to those that fall in the first category.

4.       What else?

The objections to the Classical theory, i.e. to concepts being definitions are on you. Take another look at the reading, but better think of your own intuitions and examples.

We’ll say a few words about Frege next time. It’s important that we understand the sense/reference distinction – and we will eventually. But mostly it’s gonna be Wittgenstein.

Cheers.