Let me explain a little: Certain things are bad so far as they go, such as pain, and no one, not even a lunatic, calls a tooth-ache good in itself; but a knife which cuts clumsily and with difficulty is called a bad knife, which it certainly is not. It is only not so good as other knives to which men have grown accustomed. A knife is never bad except on such rare occasions as that in which it is neatly and scientifically planted in the middle of one's back. The coarsest and bluntest knife which ever broke a pencil into pieces instead of sharpening it is a good thing in so far as it is a knife. It would have appeared a miracle in the Stone Age. What we call a bad knife is a good knife not good enough for us; what we call a bad hat is a good hat not good enough for us; what we call bad cookery is good cookery not good enough for us; what we call a bad civilization is a good civilization not good enough for us. We choose to call the great mass of the history of mankind bad, not because it is bad, but because we are better. This is palpably an unfair principle. Ivory may not be so white as snow, but the whole Arctic continent does not make ivory black.