Hi Paul,

'Set' in mathematics is taken as a primitive term with no definition... there is no connection at all between the notion of a set, or a number either for that matter, with anything real.

Well, the same thing applies to your set as applied to Tim's number. What do you mean by set? Do you mean a grouping of objects or a mathematical notation written or typed on some background [such as O(v1,...,vn).]

If you want to say that 'set' is an abstract idea and not a collection of objects (or written mathematical notation), then you must mean that it is a collection of neurons configured in such and such a manner within the brain, right? If one of the person's having this abstract idea were to get drunk or in the unfortunate case they are exposed to LSD, then what happens to their abstract notion. Can it change from one abstract idea to a different idea?