Besides inconsistency in beliefs, there’s also inconsistency in will. This leads to two further consistency requirements: ends–means consistency and conscien- tiousness.
Ends–means consistency is the requirement that we keep our means in harmony with our ends. I violate this if I (a) have an end, (b) believe that to fulfill this end I need to carry out certain means, and (c) don’t carry out the means. For example:
• I want to lose weight.
• I believe that to lose weight I need to eat less or exercise more. • I don’t eat less or exercise more.
If I combine these three, then consistency requires that I change something— that I give up my goal, or that I give up my belief, or that I follow through on the means.
Ends–means inconsistency, like inconsistency in beliefs, is common. We humans have a strong tendency to do what is easy or brings immediate satisfaction (like eat a big desert), instead of what is needed to fulfill our deeper goals. Aristotle defined a “human” as a “rational animal”; but we’re imperfectly rational, and our rational and animal dimensions can fight each other.
Inconsistency of will can occur in other ways. For example, I might make a firm resolution (to run every day), but then act against it (I keep putting it off and don’t do it). Or I might have goals (to become a doctor and to party all the time) that I realize are incompatible. Or I might violate conscientiousness.
Conscientiousness is the requirement that we keep our actions, resolu- tions, and desires in harmony with our moral beliefs. We violate this if our moral beliefs clash with how we live and want others to live.
Suppose that I hold the pacifist belief that one ought never to kill a human being for any reason. If I’m conscientious, then (a) I never intentionally kill a human being myself, (b) I resolve not to kill for any reason (even to protect my life or the lives of my family), and (c) I don’t want others to kill for any reason.
While my pacifist example is about an “ought” belief, similar requirements cover beliefs about what is “all right” (“permissible”). If I’m conscientious, then I won’t believe that something is all right without consenting to (approving of) the idea of it being done. And I won’t do something without believing that it would be all right for me to do it.
Expressed as an imperative, conscientiousness says “Avoid inconsistencies between your moral judgments and how you live.” Here’s a more specific conscientiousness imperative:
Don’t combine these two:
• I believe that I ought to do A now. • I don’t act to do A now.
If we combine these (as we often do), then our moral belief clashes with how we live—and consistency requires that we change one or the other.
“We ought to follow our conscience” could be taken in two ways: 1. We ought to avoid inconsistencies between our moral beliefs and
our actions.
2. Our conscience is always correct: if we believe that we ought to do something, then this is really what we ought to do.
The second interpretation has bizarre implications. It entails “If we believe that we ought to commit mass murder, then this is really what we ought to do.” The first interpretation, which follows our approach, is better. It simply forbids an inconsistency between our beliefs and our actions. If the two clash, then something is wrong with one or the other.
Here’s a consistency analogue of “Practice what you preach”: Don’t combine these two:
• I believe that everyone ought to do A. • I don’t act to do A myself.
This is a specific case of the general requirement to avoid inconsistencies. It doesn’t presume that our principles are correct—so that if we preach universal hatred then it becomes our duty to hate. Instead, it tells us to avoid inconsis- tencies between our principles and our actions. If the two clash, then some- thing is wrong with one or the other.
I’ve spoken of conscientiousness as a type of “consistency” between our moral beliefs and our lives. I’m leaving it open whether to take this “consisten- cy” in the specific sense of “logical consistency,” or in the more generic sense of “agreement” (or “harmony”).
Suppose my moral beliefs conflict with how I live. Prescriptivism says that I violate logical consistency (since I misuse the term “ought”). Other views might say that I violate a conscientiousness duty to keep my life in harmony with my moral beliefs; this duty might rest on a social convention, a personal ideal, a divine command, or a self-evident truth. On these views, violating conscientiousness would involve an objectionable clash between my moral beliefs and how I live, but not necessarily a logical inconsistency or self-contradiction.
Consistency is often useful in attacking flawed moral principles. Suppose that I accept the principle, “All short people ought to be beat up, just because they’re short.” My principle commits me to other things:
If I hold this: All short people ought to be beat up, just because they’re short. Then, to be consistent, I must believe that if I were short then I ought to be beat up.
And I must desire that if I were short then I be beat up.
If I don’t believe and desire these things, then I’m inconsistent and my moral thinking is flawed.