Full Idea
Imagine a person who knew everything that can be stated without using the word 'not' or some equivalent; would such a person know the whole course of nature, or would he not?
Gist of Idea
Is it possible to state every possible truth about the whole course of nature without using 'not'?
Source
Bertrand Russell (Human Knowledge: its scope and limits [1948], 9)
Book Reference
Russell,Bertrand: 'Human Knowledge' [Routledge 2009], p.111
A Reaction
Nowadays we might express Russell's thought as 'Does God need the word 'not'?'. Russell's thesis is that such words concern psychology, and not physics. God would need 'not' to describe how human minds work.
Related Idea
Idea 16488 It is hard to explain how a sentence like 'it is not raining' can be found true by observation [Russell]