more on this theme | more from this thinker | more from this text
Full Idea
Ordinary rationality is generally conservative, in the sense that you start from where you are, with your present beliefs and intentions.
Gist of Idea
Ordinary rationality is conservative, starting from where your beliefs currently are
Source
Gilbert Harman (Rationality [1995], 1.3)
Book Ref
Harman,Gilbert: 'Reasoning Meaning and Mind' [OUP 1999], p.23
A Reaction
This stands opposed to the Cartesian or philosophers' rationality, which requires that (where possible) everything be proved from scratch. Harman seems right, that the normal onus of proof is on changing beliefs, rather proving you should retain them.