 Now we consider instrumental rationality understood as a matter of rational coherence.  It is often said that someone is being locally instrumentally incoherent insofar as he intends an end, believes, roughly, that something is a means to it, but refuses to intend that means.  More precisely, it seems that this is so only when the relevant belief is about necessary means.  Suppose that I intend to go to Alaska, but believe that flying there is a sufficient, but not necessary, means to going to Alaska.  Am I being instrumentally incoherent in refusing to intend to fly there?  Not obviously: perhaps I believe that going by sea is cheaper, and I intend that.