who say they are driven to sin and death by hereditary doom. But even then the drunkard cannot be certain it was the soup, any more than the traditional drunkard who is certain it was the salmon.
Those are the facts about heredity which anyone can see. The upshot of them is not only that a miss is as good as a mile, but a miss is as good as a win. If the child has his parents' nose (or noses) that may be heredity. But if he has not, that may be heredity too. And as we need not take heredity lightly because two generations differ—so we need not take heredity a scrap more seriously because two generations are similar. The thing is there, in what cases we know not, in what proportion we know not, and we cannot know.
Now it is just here that the decent difference of function between Dr. Saleeby's trade and mine comes in. It is his business to study human health and sickness as a whole, in a spirit of more or less enlightened guesswork; and it is perfectly natural that he should allow for heredity here, there, and everywhere, as a man climbing a mountain or sailing a boat will allow for weather without even explaining it to himself. An utterly different attitude is incumbent on any conscientious man writing about what laws should be enforced or about how commonwealths should be governed. And when we consider how plain a fact is murder, and yet how hesitant and even hazy we all grow about the guilt of a murderer, when we consider how simple an act is stealing, and yet how
