Single Idea 5412

[catalogued under 12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence]

Full Idea

When a certain number of logical principles have been admitted as self-evident, the rest can be deduced from them; but the propositions deduced are often just as self-evident as those that were assumed without proof.

Gist of Idea

Some propositions are self-evident, but their implications may also be self-evident

Source

Bertrand Russell (Problems of Philosophy [1912], Ch.11)

Book Reference

Russell,Bertrand: 'The Problems of Philosophy' [OUP 1995], p.65


A Reaction

This seems an important corrective to the traditional rationalist dream, based on Euclid, that all knowledge is self-evident axioms followed by proofs of the rest. But Russell here endorses a more sensible sort of rationalism.