"Modern industry depends upon raw materials which are found at, or near, the earth's surface. These raw materials are the product of past geological ages; for the most part they are not being reproduced by any natural process. The elements were built up long ago by a process which we are just beginning to understand, and which when understood may enable clever men to put an end to the human race. The process by which the elements were built up required enormous heat, the sort of heat that exists in the interior of the sun. In a great natural laboratory, nature, starting with hydrogen, arrived by various stages at a number of elements. The number used to be ninety-two but is now indefinite. The elements, at temperatures much lower than that at which they were formed, entered into chemical combinations. At a certain stage the earth was at a temperature peculiarly suitable to the formation of complex chemical combinations, and at last combinations were formed which had the properties that are characteristic of living matter. Living matter has a curious property which I have called "chemical imperialism." In virtue of this property, when it is put into a suitable environment, it transforms a mass of dead matter into a mass of living matter. It is this property which has made organic evolution possible."