Did we but know good and evil! In the suggestion that perhaps we do not, in the suspicion that this is just the knowledge to which science does not help us,--yes, in the fear that it is science itself which throws doubt on ethical standards--is, I conceive, a motive for deprecating the progress of science more serious than the others, and more sincere. Science is, indeed, endlessly critical; no authority of tradition or of general acceptance imposes upon it; nothing for it is finished, nothing fixed; and to those to whom all goodness is in danger the moment one asks, What is good? science may well seem a dangerous growth,--unhallowed in its origin, curiosity; damnable in its outcome, unrest. And yet if as we assume science must progress, stayed neither by regret for the past nor by fear for the future, then must its questioning spirit invade every realm of opinion, examine the most sacred of beliefs, look into the very meaning of good and evil. For this reason we did well, I conceive, to begin a consideration of progress with some account of the skeptics. Science itself cannot quarrel with those who meet its advances with the question, What is the good of you? But it can only begin its answer by asking another, What do you take to be good? * * * * * What do you take to be good? Evidently there cannot be two minds, one of which points to the advance of civilization with every confidence that it means the world’s betterment, the other conceiving that men may grow wiser and none the better for that, unless _the good_ is understood by them in different senses. What are these two meanings tangled in the single word,--_the good_? It is this question that Immanuel Kant has studied with peculiar care and thoughtfulness in his ethical writings, and there he has made a distinction between two such meanings that seems very much to our purpose. The first, in his stiff academic way, he calls the _hypothetical_ use. Thus, if you were to enquire what would be the best thing to do in order to attain a certain object, your answer would recommend a certain procedure as “good,” certainly, but good only on the hypothesis that such and such is your end. Your hypothetical good washes its hands of any responsibility for what, if anything, of some other kind of good or evil may attach to your purpose; it only places its wits at your disposal in devising the best means to this end. Is your purpose to rob a bank?--Then will science set itself to think out for you the best way of robbing a bank. After that, let who will complain that bank-robbing is not a good thing to set about, he cannot deny that you have set about it in a good way.