Nor yet does personality depend upon any consciousness or sense of such personality on the part of the creature itself—it is not likely that the moth remembers having been a caterpillar, more than we ourselves remember having been children of a day old. It depends simply upon the fact that the various phases of existence have been linked together, by links which we agree in considering sufficient to cause identity, and that they have flowed the one out of the other in what we see as a continuous, though it may be at times, a troubled stream. This is the very essence of personality, but it involves the probable unity of all animal and vegetable life, as being, in reality, nothing but one single creature, of which the component members are but, as it were, blood corpuscles or individual cells; life being a sort of leaven, which, if once introduced into the world, will leaven it altogether; or of fire, which will consume all it can burn; or of air or water, which will turn most things into themselves. Indeed, no difficulty would probably be felt about admitting the continued existence of personal identity between parents and their offspring through all time (there being no _sudden_ break at any time between the existence of any maternal parent and that of its offspring), were it not that after a certain time the changes in outward appearance between descendants and ancestors become very great, the two seeming to stand so far apart, that it seems absurd in any way to say that they are one and the same being; much in the same way as after a time—though exactly when no one can say—the Thames becomes the sea. Moreover, the separation of the identity is practically of far greater importance to it than its continuance. We want to be ourselves; we do not want any one else to claim part and parcel of our identity. This community of identities is not found to answer in everyday life. When then our love of independence is backed up by the fact that continuity of life between parents and offspring is a matter which depends on things which are a good deal hidden, and that thus birth gives us an opportunity of pretending that there has been a sudden leap into a separate life; when also we have regard to the utter ignorance of embryology, which prevailed till quite recently, it is not surprising that our ordinary language should be found to have regard to what is important and obvious, rather than to what is not quite obvious, and is quite unimportant.