What, then, is the probable essence of truth in Professor Haeckel's philosophy? for it is not to be supposed that the speculations of an eminent man are baseless, or that he has been led to his view of what he conceives to be the truth by some wholly erroneous path; his intuitive convictions are to be respected, for they are based on a far wider experience and knowledge of fact than is given to the average man; and for the average man to consider it likely that there is no foundation whatever for the life convictions of a great specialist is as foolish as to suppose it probable that they are certain and infallible, or that they are uncritically to be accepted even in regions beyond those over which his jurisdiction extends. First as to the "law of substance," by which he sets so much store; the fact which he is really, though indistinctly, trying to emphasise, is what I have preferred to formulate as "the persistence of the really existent," see page 34; and, with that modification, we can agree with Haeckel, or with what I take to be his inner meaning, to some extent. We may all fairly agree, I think, that whatever really and fundamentally _exists_ must, so far as bare existence is concerned, be independent of time. It may go through many changes, and thus have a history; that is to say, must have definite time relations, so far as its changes are concerned; but it can hardly be thought of as either going out of existence, or as coming into existence, at any given period, though it may completely change its form and accidents; everything basal must have a past and a future of some kind or other, though any special concatenation or arrangement may have a date of origin and of destruction.