THE ORGANISM AND ITS ORIGIN

"What is life ? ", "What is an organism ? " and "How did life originate ? " are questions of fundamental importance. Answers to these questions form the basis of the subject matter of biology; and until man discovers these solutions, his knowledge of biology must remain fragmentary and unsatisfying. To assert that the solutions of these problems will resolve all questions in biology is probably false; however, if biology is a science distinct from chemistry and physics, and if biological phenomena are based on chemical and physical phenomena, then presumably a group of assumptions, definitions and principles exist which unify biology and set it apart from all other science. That this set of definitions and assumptions is intimately related to these questions seems highly probable. The purpose of this paper is to investigate this probability. Answers to the first question have been proposed by but a few men in recent times. For example, Osborn (1917) proposes that life depends in part on the activities of the developing organism and its hereditary material and in part on the environment. This view later became the organismal theory of life. Calkins (1933) states that "life may be defined as protoplasmic organization manifesting vitality or a potential of vitality" and defines "vitality, therefore, as the sitm total of actions, reactions and interactions between and amongst the substances makintg up the organization of protoplasm and between these and the environment" (p. 47, italics his). These definitions are cyclic and may be restated as: life is protoplasm behaving as protoplasm. Many biologists consider life too complex to define and substitute for a definition a list of characteristics common to all organisms. The use of such a list is unsatisfactory because (1) non-living systems frequently exhibit one or more of these characters, (2) seldom, if ever, does an organism manifest all of these attributes at one time, and (3) the characters can be demonstrated in some organisms, such as the viruses and some bacteria, with difficulty. Both Troland and Alexander and Bridges (Alexander, 1948) consider the attributes of life; and Alexander asserts: 'fThe essential criteria of life are twofold: (1) the ability to direct chemical change by catalysis; (2) the ability to reproduce by autocatalysis" (p. 88). Although "the essential criteria of life" appear to solve the problem of what life is in a very neat and simple manner, closer examination of them raises serious questions. Systems of purified enzymes and substrates can be set up which satisfy the first criteria but not the second; are these alive? If the answer is no, then is life synonomous with the second criterion? Other workers propose answers to the question, "What is life? ", which depend upon the organism as a whole, organization, vitalism, or purpose (Lillie, 1945; Sommerhoff, 1950; Sinnott, 1950); or even suggest that life is subject to a different set of physical laws than is nonliving matter (Schr6dinger, 1947). However, not one of these suggestions has been developed to serve as a basis for the field of biology. Pirie (1937), while considering the qualities to define the word life, finds that "they are individually inadequate for even an approximate definition . " and proposes that "until a valid definition has been framed it seems prudent to avoid the use of the word 'life' in any discus-