Summary of Collins A.: ON THE QUESTION ‘DO NUMBERS EXIST?’ in The Philosophical Quarterly, Vol. 48, No. 190 (1998). pp. 23-36
1.0 Introduction
In human thought, the numbers appear to have originated from the various physical situations encountered by man – the difference between a herd and a goat, the difference between 3 deers and 1 deer, the correspondence between number of shadows and number of people etc. At some point, the abstract property which is common to say two groups (ex. 5 arrows and 5 birds) was recognized and this is what is called a number. This is a primitive notion of a number, in contemporary times we have various kinds of numbers – the rationals, the irrationals, the imaginary numbers etc. But all the kinds of numbers are equally abstract. So the question arises, where does the number exist or do they exist at all. The paper is an attempt to this question. The author treats the problem as of having a linguistic origin. The author rejects the usual answers to the problem that is realism and nominalism, so first I will explain these usual answers in brief before presenting authors views.
2.0 Realism and Nominalism
“Realism is a philosophy of mathematics and an ontological commitment” (Collins, pp23). That is, realism is the belief that properties, usually called Universals, exist independently of the things that manifest them. Therefore, if we remove all the rectangular shaped objects from the universe, still the universal rectangle will exist. Thus it can be seen that there are two aspects to realism. First, there is a claim about existence. The billiard tables, the football grounds, the books exist and so does the rectangleness. The second aspect of realism concerns independence. The fact that the billiard table exists and is rectangular is independent of anything anyone happens to say or think about the matter. The question of the nature and plausibility of realism is a controversial issue (Miller, 2002).
Nominalism is an anti-realist stand. The doctrine holding that abstract concepts, general terms, or universals have no independent existence but exist only as names. The relation between universal and name is conventional.
But there is a problem with nominalism as pointed out by Prof. Gomatam during the class discussion; it is the fact that a universal say rectangleness cannot be attributed to arbitary things, so universals are not just names.
3.0 The short argument
It is a familiar thought that we might posit numbers to explain the known arithmetical truths and scientific truths the expression of which requires numerical representation (Collins, pp. 23). To explain this author gives an example,
There are four prime numbers smaller that 8.
Quine is a soft realist. As quoted by Putnam, Quine thinks it is intellectual dishonesty to use and talk about mathematical entities, yet deny their existence. Quine treats everything as a myth, but he treats the myth of physical objects as superior to say Homer’s gods. He says, “…The myth of physical objects is epistemologically superior to most in that it has proved more efficacious as a device for working a manageable structure into the flux of experience”. Hartry Field also has a similar view. If believes that if numbers can be shown to be a useful myth then it can be shown that they are fictional thus, they do not exist.
4.0 Linguistic solution
Author says that short argument is sufficient to show the existence of numbers but the question about the way they exist, should not be asked as it is inappropriate. He accepts that numbers do not exist as the physical objects do, still it is right to say that they exist. As pointed by Prof. Gomatam, it seems what author wants to say is that by asking the question about way the numbers exist, we are making a category mistake. For example, if pen is in the pocket, we can ask someone to pull it out. Whereas, if someone says, he has an idea in his head we do not ask him to pull it out.
5.0 Conclusion
Although, I am unable to agree that the short argument is sufficient to establish the existence of numbers. But I am inclined to believe that the numbers exist based on Quine’s argument. Field also recognizes that Quine’s argument is the strongest argument for realism. Quine argues that it is indispensable to talk about mathematical entities yet their existence is denied which implies that there is an intellectual dishonesty. Yet, the question of about what is for them to exist is not answered. Author argues that the question is wrong because our discourse with numbers does not generate the question. Also, because of the fact that the numbers are given negative attributes, the question of what is for them to exist sounds wrong to me.
6.0 References:
1. Miller, A (2002), Stanford Encyclopedia of Philosophy, http://setis.library.usyd.edu.au/stanford/entries/realism/.
2. Collins, A.(1998, ON THE QUESTION ‘DO NUMBERS EXIST?’ in The Philosophical Quarterly, Vol. 48, No. 190 pp. 23-36.