The self-evidence Ross attributes to moral propositions is weaker in that whereas on (SE) a self-evident proposition will be evident for any person who understands it, according to Ross a self-evident moral proposition is evident for any person who has attained sufficient mental maturity and given the proposition sufficient attention. Hence, on Ross’s conception, a self-evident proposition, PSE, might not be justified for some, and perhaps even many, who understand it; PSE may not be evident to