more from Thomas Mautner

Single Idea 4782

[catalogued under 14. Science / C. Induction / 5. Paradoxes of Induction / b. Raven paradox]

Full Idea

If observing a white sheet of paper confirms that 'all non-black things are non-ravens', and that is logically equivalent to 'all ravens are black' (which it is), then the latter proposition is confirmed by irrelevant observations.

Gist of Idea

'All x are y' is equivalent to 'all non-y are non-x', so observing paper is white confirms 'ravens are black'


report of Thomas Mautner (Penguin Dictionary of Philosophy [1996], p.105) by PG - Db (ideas)

Book Reference

Mautner,Thomas: 'Dictionary of Philosophy' [Penguin 1997], p.105

A Reaction

This seems to me more significant than the 'grue' paradox. If some observations can be totally irrelevant (except to God?), then some observations are much more relevant than others, so relevance is a crucial aspect of induction.