and whether really between the two the miracle of the creation out of nothing has repeated itself millions of times, in order to work just as often into the hands of absolute annihilation. I know well that if I seriously assured any one that the cat which now plays in the yard is still the same one which made the same springs and played the same tricks there three hundred years ago, he would think I was mad; but I also know that it is much madder to believe that the cat of to-day is through and through and in its whole nature quite a different one from the cat of three hundred years ago. One only requires truly and seriously to sink oneself in the contemplation of one of these higher vertebrates in order to become distinctly conscious that this unfathomable nature, taken as a whole, as it exists there, cannot possibly become nothing; and yet, on the other hand, one knows its transitoriness. This depends upon the fact that in this animal the infinite nature of its Idea (species) is imprinted in the finiteness of the individual. For in a certain sense it is of course true that in the individual we always have before us another being – in the sense which depends upon the principle of sufficient reason, in which are also included time and space, which constitute the principium individuationis. But in another sense it is not true – in the sense in which reality belongs to the permanent forms of things, the Ideas alone, and which was so clearly evident to Plato that it became his fundamental thought, the centre of his philosophy; and he made the comprehension of it the criterion of capacity for philosophising in general.
As the scattered drops of the roaring waterfall change with lightning rapidity, while the rainbow, whose supporter they are, remains immovably at rest, quite untouched by that ceaseless change, so every Idea, i.e.,every species of living creature remains quite untouched by the continual change of its individuals. But it is the Idea, or the species in which the will to live is really rooted, and manifests itself; and therefore also the will
