Let us consider for a moment what it is for a man to be wise—to be the sort of person to whom we naturally turn for advice when faced with a moral difficulty. The word ‘wise’ is obviously evaluative; we shall not, on reflection, call a man wise unless we agree with the content of the moral advice he has given us—after we have seen the consequences of carrying it out, or disregarding it. But what is it in a man which leads us to expect that we shall be able, after the event, to say that his advice was wise? If I were seeking for advice in such a situation, I should look first for a man who had himself experienced difficulties of an analogous sort to mine. But this would not be enough; for the quality of the thought that he had given to these situations might have been poor. I should look also for a man of whom I could be sure that in facing moral questions (his own or mine) he would face them as questions of moral principle and not, for example, as questions of selfish expediency. This means that I should expect him to ask, of his own actions, ‘To what action can I commit myself in this situation, realizing that, in committing myself to it, I am also (because the judgement is a universalizable one) prescribing to anyone in a like situation to do the same—in short, what can I will to be a universal law?’. If I could find a man whom I knew to have been confronted with difficult choices, and whom, at the same time, I could expect to have had the courage to ask moral questions about them (not, to use Sartre‘s words, to ‘conceal from himself the anguish’ of universalization), then that would be the man whose advice I should gladly seek, if it were moral advice that I wanted. And I should not expect him to produce quickly some simple maxim; he would, no doubt, find it extremely hard to formulate in words any universal proposition to cover the case. But I should be sure that he would consider the particular case carefully and sympathetically in all its details, and after doing that try to find a solution to which I could commit, not only myself, but, as Sartre again puts it, ‘the whole of humanity’.

(R. M. Hare, Freedom and Reason [Oxford: Clarendon Press, 1963], 47-8 [italics in original; parenthetical citation and footnotes omitted])