EMERGENCE. The difference between a mechanical mix ture and a chemical compound was among the first things to which the attention of one who entered a laboratory more than half a century ago was directed. He was shown finely pulverized charcoal and sulphur where the relative proportions varied between the limits of o and I00% of sulphur. He was then shown the chemical compound labelled CS,. He was bidden to note the very different effect this produces on the senses. He was taught more about it ; the unvarying percentage of sulphur ; how light waves behave as they pass through it ; what happens when it is heated ; and so on. He learnt in picturesque and imaginative fashion something of its intimate structural organization. He was led to realize that in some way this structure is connected with certain properties and qual ities; to realize also that carbon bisulphide comes into being pretty suddenly under certain conditions and not otherwise.
In the Second Series of Problems of Life and Mind (1875) George Henry Lewes suggested a new name—not a new concept. That which, under such conditions, springs into being he called "emergent." He held that the nature of an emergent cannot be foretold from the nature of its several constituents as they are in themselves prior to Emergence. Hence the nature of an emer gent can be known only through observation and experiment when that emergent has come into being. He contrasted emergents with "resultants." The nature of a mixture of charcoal and sulphur, as resultant, can be foretold from the nature of the assembled particles. In such a resultant there is not a new and unforeseen mode of structural organization; nor is there a new and unforeseen set of properties.
If the word "Emergence" be taken over from Lewes it should be used in the sense he intended. He distinguished between an "empirical" treatment of nature and one that he called "metem pirical" (1873) seeking thus to avoid the ambiguities of the word "metaphysical." What he meant by empirical treatment is one which is in accordance with the methods of inductive science. If, on the evidence of observation and experiment, there be Emer gence, this is to be taken as it is given in nature, leaving others to discuss its alleged introduction into nature through some "metem pirical" influx. On these terms, which are here accepted, Emer gence is a hypothesis of inductive science to be weighed on the available evidence. There can be little doubt that Lewes would have regarded emergent evolution as empirical, and creative evo lution as typically "metempirical." When we apply the distinguishing analysis and synthesis of modern scientific thought to a crystal, that we may piece together its story, it comes, in brief, to this : The proximate constituents are crystal units. The crystal as a whole is, for our unaided vision, the visible and tangible expression of one of a limited number of ways in which these crystal units go together. Under further analysis (distinguishing not destructive) each crystal unit is made up of molecules which go together in a distinctive mode of structural organization; each molecule is made up of atoms which go together in a distinctive way ; each atom is made up of electrical charges in proton and electrons; and they too go together in a distinctive manner. .
Here we still keep in the neighbourhood of Lewes's starting point. But we concentrate attention on structural organization, in the crystal unit, in the molecule, and in the atom. Now it may be that tJie distinctive plan of crystal-organization can be foretold from that of molecular organization, and this from the atomic plan. If this be so the crystal unit is interpretable as the outcome of resultant advance. Or it may be that the crystal unit cannot be foretold from the molecule, nor the molecule from the atom. If that be so each new mode of organization exemplifies Emergence. Of course in either case what actually happens can be generalized after the event under so-called "natural laws." There seem, then, to be two alternative hypotheses. The alter natives are: (I) All events within the crystal are susceptible of resultant treatment (suitably defined) ; some events within the crystal are emergent. In discussing the evidence in support of this hypothesis or that, one must get at the facts of observation and experiment as these facts are interpreted by the scientific ex pert on the lines of inductive procedure. But we must turn to the logician to say whether it is possible or impossible to foretell the organization of the crystal on the basis of our knowledge of the molecule. To carry the matter yet further, we may ask the experi mentalist and the logician to combine forces and tell us whether the whole inorganic world can or cannot be deduced on the basis of our knowledge of, say, the Bohr-Rutherford atom.
The discussion is in progress in the light of present scientific knowledge. It may well be that the advance of knowledge will change the existing position of affairs. But to say that, though not yet, still some day, all events within the crystal, as a sample of the inorganic world, will be shown to be deducibly "resultant," is to anticipate the verdict of the future. We cannot foretell how mat ters may stand ten years hence. But whatever the verdict of the future may be, the concept of Emergence does here and now raise a crucial question.
But a question wholly different in kind may be raised. It may be asked : How is one to account for the sudden or very rapid ap pearance of new modes of structural organization with which are connected new properties and qualities? The only way in which the man of science professes "to account for" anything that hap pens is by describing in generalized terms the observed conditions under which it does happen. In this sense those who accept Emer gence are bound to render the fullest possible account of these conditions in each instance of its alleged occurrence. It is in this sense that the words "account for" should be used in discussing Emergence as a scientific hypothesis. One does not in science ac count for the crystal by invoking an extraneous "somewhat" to be discussed in terms of "crystalism." If we apply distinguishing analysis to the living organism, we come down, when we probe deep enough, to molecules and atoms. But some of the molecules—for example, those of the amino acid constituents of protein—are organized in a special many-linked way. If this distinctive plan of organization can be foreseen on the basis of our knowledge of simpler modes of molecular organization the amino acids, or more comprehensively the biochemical constit uents of protoplasm, exemplify resultant advance. But if they cannot be foreseen they exemplify Emergence.
In this field of enquiry the man of science seeks to account for what happens by stating the observable conditions under which it does happen in the living organism or perhaps in the laboratory—. not by invoking an extraneous "somewhat" to be discussed by philosophers in terms of "vitalism." Closely connected with the structural organization and proper ties of protoplasm there are those processes in the living organism with which it is the task of physiology to deal. Here also for science the question is : Are all the events within the living organ ism susceptible of resultant treatment ; or are some of these events such as to exemplify Emergence? This is a plain issue.
And when we pass to mental affairs the issue for science is like in kind. On the one hand we have such dim sentience and percip ience as may be attributed to the amoeba; on the other hand we have such higher modes of mentality as we attribute to man. Dis tinguish, say, three stages : percipience, perception, reflective thought. Then ask : Is the mode of organization in reflective thought predictable from that in perception, and that in percep tion from amoebiform percipience? Or is Emergence exemplified in mental advance no less than in physiological advance and in the advance of events throughout nature? What we need, in the ad mittedly abstract domain of science, is an evaluation of the evi dence in support of Emergence, and its treatment from the stand point of logic.