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Dealing With The Exception
The exception is perhaps the greatest obstacle for any moral theory to deal with. You adopt a supposedly ideal moral system which should tell you what to do to act morally in any possible case: all you have to do is deduce the proper action from your principle or set of principles, then follow it. No problem. You’ll be doing the right thing, and acting without sin. But then you run into that odd, unexpected situation where following your rulebook doesn’t seem so neat and tidy. This new case is special, unique, and unanticipated by your ethical system. In fact, it just feels wrong to follow the rules here in this instance. Do you go with your rulebook, or your current intuition?
There are many who would step in and try to defend principled (rulebook style) ethics. They have three obvious defenses:
(1) Simply deny that apparent problems create exceptions.
(2) Hold the view that principles can be rewritten so that the apparent exceptions are no longer exceptions.
(3) Argue that each apparent exceptional case is really a case of conflicting principles, where two or more principles both apply, but one is overruled by another of greater priority.
Why You Shouldn’t Be A Person Of Principle,
Ramsey McNabb, Philosophy Now