The works of Teilhard de Chardin, now being published posthumously, appear to be having a considerable impact on certain sections of the Catholic community on the Continent. The time is hardly ripe yet for the publication of a full critical appraisal of his writings, and the author of this book would not pretend that it is more than an introduction to Teilhard himself, with an exposition of certain features of his writings which appear particularly to call for critical comment. More important at this stage than commentaries, is that the works themselves should be read and talked about. Slowly, then, by constant usage, we shall extract more and more meaning out of those brilliant new words and phrases that Teilhard has introduced into the study of the history of the world: words such as enroulement, to describe the essential feature of the evolutionary process (compare the traditional déroulement); and hominisation, to indicate the unquestioned tendency in evolution, especially in the Vertebrates, for increasing elaboration of the central nervous system without which, so far as we can see, those characteristics which we recognize as essentially human would not be possible. Hominisation becomes, then, the end of the evolutionary process, for it is admitted by not a few biologists today that, of all the species now extant, it is Homo sapiens alone which is capable of making any further major evolutionary advance. This is attributed by Teilhard precisely to Man’s spiritual capacities by virtue of which, in continuation of the process of enroulement, he is offered the possibility (one species representing all the rest) of discovering at the heart of all creation the Omega, present there from the beginning as the Alpha.