Now, this principle is called the principle of correspondences. You find it, as I said, used by Mystics of all types in the past: the great scientist-mystic, Swedenborg, of Sweden, based a very large part of his thought on the system of correspondences, of trying to discover what was far off and extensive by a study of that which was near and comparatively small. So in our own day with regard to science; and I remind you first of that in order to show you that in using this principle we are on ground which is recognised as being firm and stable, and is adopted in all the greater researches which have to deal with the distant and the extensive. Science has made specially good use of this system of correspondences in two lines of its thought: one, that of evolutionary growth, illuminated by the study of embryology; the other, that of the evolution of consciousness in humanity at large, illuminated by an observation of consciousness in the child, the youth, and the man. If, for a moment, we stop on the great evolutionary series or cycles of the past, we shall at once recognise that direct observation is only possible to a very small extent. It is true that by the aid of geology many buried skeletons of the past may be brought to the surface and examined, and thus light may be thrown on the various classes to which the skeletons in the time of the living animal belonged. Fossil remains certainly help us to a very great extent in trying to study the evolutionary past of our globe; but, as everyone knows who has studied the geological record, that record has large gaps occurring in it from time to time. It is exceedingly imperfect, exceedingly unsatisfactory, and only along some limited lines of evolutionary study is it possible to find from the fossils of the past the principle of life as it has gradually grown and branched upon our earth. Hence, in the difficulty of thus unveiling the past, evolutionists have turned to the study of the near, the growth of the individual, the stages through which his body passes, especially during ante-natal life, and it was very largely the study of embryology that threw light on the evolutionary truth. For it is observed, in tracing the growth of the human body of the individual, that it passes through certain clear, definite, marked stages. There is a stage at which the characteristics are those of the fish, bringing about some very curious results as regards especially the distribution of some of the nerves; then a stage which is that of the reptile; then a stage which is that of the mammal; and so on up to the highest in the mammalian kingdom, man himself. From the standpoint of mere observation from outside, without use of reason, this sequence invariably followed would say little, would signify little; but when man looks at that with the eye of reason, and not only observes the succession of certain stages, but applies his reason to solve the problem as to why those stages constantly