Some have said that ‘can’s are constitutionally iffy. On a simple version of this view, to say that someone could have done otherwise is just to say that if he had chosen to do otherwise, then he would have done otherwise. Chisholm points out ([P&amp;O], 56–7) two reasons why this is wrong. First, suppose the person was capable of traveling in any direction and easily could have gone to Boston; but suppose in addition that he did not know the way to Boston. If he had chosen to go to Boston, he would have ended up in New London. Then it is correct to say that he could have gone to Boston, but incorrect to say that if he had chosen to go to Boston, he would have done so. Secondly, suppose the person is incapable of choosing to go to Boston. Maybe he is overwhelmed with fear of Boston. But if nothing else prevents the trip, it will be correct to say that if he had chosen to go to Boston, he would have gone, but it is incorrect to say that he could have gone to Boston.