complexity. There is, moreover, every indication from the results of biological investigation of recent years that the continuous changes in the vital processes proceed according to law, and although according to a law at present unknown, yet not necessarily unknowable. In the understanding of this problem the frontiers of our knowledge have been pushed forward in a most astonishing manner, and by methods and hypotheses which are essentially intelligible. It is not a new logic that is needed, but further advances of the old. The complexity of the processes is being reduced to simpler and simpler terms. In the rapid progress of experimental results in biology, there is not the faintest suggestion that the processes of evolution are in any sense capricious or lawless.
The most complex of all the processes of life, that of the continuous development of the race in unbroken line from generation to generation, has been simplified to an extent which a decade ago it would have been impossible even to conceive, by the rediscovery in 1900 of the work of Mendel, and the formulation of the Mendelian law. This marked the era of the introduction of order into a confused mass of biological phenomena.
Bateson in his essay on "Heredity and Variation in Modern Lights" speaks of this discovery in a most significant manner as follows: "Those who had a preliminary acquaintance with the facts of Variation were not wholly unprepared for some such revelation. The essential deduction from the discovery of segregation was that the characters of living things are dependent on the presence of definite elements or factors, which are treated as units in the processes of Heredity. These factors can thus be recombined in various ways. They act sometimes separately, and sometimes they interact in conjunction with each other, producing their various effects. All this indicates a definiteness and specific order in heredity, and therefore in variation. This order cannot by the nature of the case be dependent on Natural Selection for its existence, but must be a consequence of the fundamental chemical and physical nature of living things. The study of Variation had from the first shown that an orderliness of this kind was present. The bodies and properties of living things are cosmic, not chaotic. No matter how low in the scale we go, never do we
