For us who accept Mortal Life and say “Yea” to it wholeheartedly, there are certain very grave duties too. The thing to which we say “Yea,” we wish to keep both clean, sweet and alluring. This world is our home, and we take a pride in it. We must make it such that we are able to take a pride in it. We recognize that Mortal Life includes pain as a prominent factor; but, provided that pain is practically inseparable from the best purposes of life (as, for instance, the pain of self-discipline, self-mastership, the pain of habituation to new knowledge, new arts, the pain resulting from the natural relationships to our myriads of fellows, and the pains of child-birth), we say “Yea” to it too, and with the same wholeheartedness. We do not shrink from pain, as Schopenhauer did, we do not magnify it or concentrate upon it, as he did, and condemn the whole of existence because of it. We do not call our glorious history, as the King of the Animals, the _Martyrdom of Man_, as Winwood Reade did. We call our history the _Triumph of Man_; and it is because we wish to maintain it as the triumph of man that we face it with spirit and positiveness. Our duties are grave, I say; they involve everything, in fact, that can be conceived as belonging to the task of keeping that to which we say “Yea” in the highest degree worthy of our “Yea”—worthy, that is to say, of our unreserved acceptance. The conduct of Mortal Life, therefore, is our principal concern. And for this conduct to be correct and fruitful in good things, we must be quite clear as to the “shall” and the “shall not” of what we should hate and what we should love, of what we should call bad, and what we should call good. Throughout this book the word “good” will always mean “_that which is favourable to the best kind of Mortal Life and its multiplication_.” If this book reveals any hate at all, it will be for that which is hostile to the best kind of life, and if it reveals any love at all it will be for everything that is friendly to the best kind of life. This takes us far, no doubt; but not farther, I believe, than anyone should wish to go who has said “Yea” honestly and sanguinely to Mortal Life. For instance, in opposition to men like St. Paul, Knox, Calvin, Prynne, Schopenhauer, Otto Weininger and their like, we say that Sex is good, Woman is good, the flesh is good. And we heartily dislike men like St. Paul, Knox, Calvin, Prynne, Schopenhauer and Otto Weininger because their attitude shows not only hostility to Woman and to Sex, but also, by implication, to Mortal Life, to which we have said “Yea.”