To: Matthew M.
From: Geoffrey Klempner
Subject: Berkeley's attack on abstract ideas
Date: 24th March 2010 12:15

Dear Matthew,

Thank you for your email of 15 March, with your essay for the University of London BA Modern Philosophy: Descartes et. al. module, in response to the question, 'Why was it important to Berkeley to attack the theory of abstract ideas? How successful is his attack?

This is a fair answer to the question, and also a good length for a one hour examination answer. However, it is a bit short of the 2000-2500 word target that I have asked for. I had the feeling that you couldn't think of much more to say -- which is generally a sign that there is something about the topic that you don't fully 'get'.

There is a general problem with the 'modular' approach to the BA, in that you will be answering questions, e.g. on Modern Philosophy which would greatly benefit from knowledge of other areas of philosophy, or other philosophers covered in modules which you haven't taken. This particularly applies to the present case, as the issue of 'what it is to grasp a concept' is one of the preoccupations of 20th century philosophy of language, and a key feature of the later philosophy of Wittgenstein.

For similar reasons (as I remarked to another UoL student recently) it helps with the Modern Philosophy module if you have read a bit about Kant, who has deep and very pertinent criticisms to make of Descartes, Locke and Berkeley.

In the 20th century, Locke's account of how we 'abstract' ideas or concepts from experience has come under attack from two directions.

The first questions the coherence of the genetic assumption that we arrive at concepts through a process of abstraction: e.g. a child learns 'red' by being shown different red things, or 'round' by being shown different round things. Peter Geach in his book 'Mental Acts' argues that this gets the order wrong. In the process of learning language, we learn how concepts interconnect at the same time as we learn particular instances of their application. You need to have the concept of 'round' in order to be able to register that a ball, a tomato, the moon are all round. How is that possible? Round is a concept of geometry which we learn concurrently with learning names for other shapes. And where do we get the concept of shape? By being shown different objects with different shapes, and abstracting what they have 'in common'? Evidently not. In other words, Locke represents the process as a linear series of mental actions, when in fact it is more complex and essentially bound up with language acquisition.

The idea that concepts are entities existing in the head, or in particular that concepts are some kind of model or picture or image comes under attack from Wittgenstein in 'Philosophical Investigations' in his account of what it is to follow a rule. Both Platonism (the belief that concepts exist in Plato's World of Forms) and psychologism (the Lockean view) beg the question because applying a model or a picture or an image to the external world itself involves following a rule. We may think it is obvious that a sign with a sharp end 'points' in the direction of the sharp end, but that's just a convention. We learn to 'read' signs that way. There might be a country somewhere where signs are read the opposite way. Suppose you wanted to draw a diagram showing the correct way to read a sign. How do we read the diagram? Again, following a rule is essentially bound up with language knowledge and use.

So in some respects it could be said that in attacking Locke, Berkeley shows himself to be more acutely aware of the problem of explaining how we use and acquire concepts, or how we are able to follow a rule. The notion that a particular idea becomes 'general in its signification' does not, however, look very useful as an alternative account of how we grasp that general signification. The bad explanation is thrown out, but what remains merely seems to beg the question.

You are right that Berkeley's critique seems to acquire greater force if we assume an 'imagist' notion of ideas or concepts. However, psychologism like Platonism isn't wedded to the literal notion of an 'abstract image'. The idea that Plato believed, for example that the Form of Horse IS in some sense a horse (or 'looks' like a horse) came under attack from Plato himself in the '3rd Man' argument in the dialogue 'Parmenides'. In other words, Plato (at least, in his late philosophy) seems to have been fully aware that the notion of Forms as paradigms must not be taken too literally. Even so, Forms or ideas or concepts, be they in Plato's heaven or in your head, are being asked to do to much work if we think that they somehow embody a complete recipe for correct application of a general word.

You mention the main reason why Berkeley 'needed' to attack the theory of abstract ideas, namely, that Locke's doctrine aids and abets the illicit attempt to form a notion of perceptual objects existing unperceived. It is worth noting also that Berkeley uses the same line of argument against Locke's primary/ secondary quality distinction. But, as you say, this is less than compelling as an argument for Berkeley's immaterialism. There might indeed (from Berkeley's perspective) be more than one possible explanation of why we fall into the fallacious belief in the existence of 'matter'.

All the best,

Geoffrey