Litany of Blume

Your beliefs clash with reality? Change your beliefs. This is what beliefs are for. Can't do this? May as well not bother having beliefs.
Your morals conflict with reality? Change reality. This is what morals are for. Can't do this? May as well not bother having morals.

—Michael Blume

The litany is accompanied by this note by Blume:

Note though, relation isn't transitive. If your morals conflict with your beliefs, chances are you need to change reality, not beliefs.