But of course the great difference between Aristotle and the moderns, is that the former did not guess, what the latter have discovered, namely that evolution is not only a logical development, but is a fact in time. Aristotle knew what was meant by the higher and lower organism as well as Darwin, but he did not know, that the latter {309} actually turns into the former in the course of years. But this, though the most obvious, is not really the most important difference between Spencer and Aristotle. The real difference is that Aristotle penetrated far more deeply into the philosophy of evolution than modern science does; that, in fact, modern science has no philosophy of evolution at all. For the fundamental problem here is, if we speak of higher and lower beings, what rational ground have we for calling them higher and lower? That the lower passes in time into the higher is no doubt a very interesting fact to discover, but it dwindles into insignificance beside the problem just indicated, because, on the solution of that problem it depends whether the universe is to be regarded as futile, meaningless, and irrational, or whether we are to see in it order, plan, and purpose. Is Spencer's doctrine a theory of development at all? Or is it not rather simply a theory of change? Something resembling an ape becomes a man. Is there development here, that is, is it a movement from something really lower to something really higher? Or is it merely change from one indifferent thing to another? Is there improvement, or only difference? In the latter case, it makes not the slightest difference whether the ape becomes man, or man becomes an ape. The one is as good as the other. In either case, it is merely a change from Tweedledum to Tweedledee. The change is meaningless, and has no significance.