Combining Texts

Ideas for 'From an Ontological Point of View', 'The Principles of Mathematics' and 'On the Introduction of Transfinite Numbers'

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6 ideas

2. Reason / B. Laws of Thought / 6. Ockham's Razor
A theory with few fundamental principles might still posit a lot of entities [Heil]
     Full Idea: It could well turn out that a simpler theory - a theory with fewer fundamental principles - posits more entities than a more complex competitor.
     From: John Heil (From an Ontological Point of View [2003], 13.6)
     A reaction: See also Idea 4036. The point here is that you can't simply translate Ockham as 'keep it simple', as there are different types of simplicity. The best theory will negotiate a balance between entities and principles.
Parsimony does not imply the world is simple, but that our theories should try to be [Heil]
     Full Idea: A commitment to parsimony is not a commitment to a conception of the world as simple. The idea, rather, is that we should not complicate our theories about the world unnecessarily.
     From: John Heil (From an Ontological Point of View [2003], 13.6)
     A reaction: In other words, Ockham's Razor is about us, not about the world. It would be absurd to make the a priori assumption that the world has to be simple. Are we, though, creating bad theories by insisting that they should be simple?
2. Reason / D. Definition / 13. Against Definition
Definition by analysis into constituents is useless, because it neglects the whole [Russell]
     Full Idea: A definition as an analysis of an idea into its constituents is inconvenient and, I think, useless; it overlooks the fact that wholes are not, as a rule, determinate when their constituents are given.
     From: Bertrand Russell (The Principles of Mathematics [1903], §108)
     A reaction: The influence of Leibniz seems rather strong here, since he was obsessed with explaining what creates true unities.
In mathematics definitions are superfluous, as they name classes, and it all reduces to primitives [Russell]
     Full Idea: The statement that a class is to be represented by a symbol is a definition in mathematics, and says nothing about mathematical entities. Any formula can be stated in terms of primitive ideas, so the definitions are superfluous.
     From: Bertrand Russell (The Principles of Mathematics [1903], §412)
     A reaction: [compressed wording] I'm not sure that everyone would agree with this (e.g. Kit Fine), as certain types of numbers seem to be introduced by stipulative definitions.
2. Reason / F. Fallacies / 2. Infinite Regress
Infinite regresses have propositions made of propositions etc, with the key term reappearing [Russell]
     Full Idea: In the objectionable kind of infinite regress, some propositions join to constitute the meaning of some proposition, but one of them is similarly compounded, and so ad infinitum. This comes from circular definitions, where the term defined reappears.
     From: Bertrand Russell (The Principles of Mathematics [1903], §329)
2. Reason / F. Fallacies / 8. Category Mistake / a. Category mistakes
As well as a truth value, propositions have a range of significance for their variables [Russell]
     Full Idea: Every proposition function …has, in addition to its range of truth, a range of significance, i.e. a range within which x must lie if φ(x) is to be a proposition at all, whether true or false. This is the first point of the theory of types.
     From: Bertrand Russell (The Principles of Mathematics [1903], App B:523), quoted by Ofra Magidor - Category Mistakes 1.2
     A reaction: Magidor quotes this as the origin of the idea of a 'category mistake'. It is the basis of the formal theory of types, but is highly influential in philosophy generally, especially as a criterion for ruling many propositions as 'meaningless'.