Mr. Potter, in the end people all do what they want to do. Sometimes people gives names like 'right' to the things they want to do, but how could we possibly act on anything but our own desires?
-- Rational!Quirrel, HPMoR chapter 20
In other words: how else can you justify a moral belief and consequent actions, except by saying that you really truly believe in your heart that you're Right?
We should not confuse between the fact that almost all people other than Manson think he was morally wrong, and the fact that his justification for his action seems to me to be of the same kind as the justifications anyone else ever gives for their moral beliefs and actions.
Unlike Quirrell, Penn Jillette is not referring to "knowing in your heart" that your moral values are correct, but to "knowing in your heart" some matters of fact (which may then serve as a justification for having some moral values, or directly for some action).
Another month has passed and here is a new rationality quotes thread. The usual rules are:
And one new rule: