A COMPENDIOUS CLASSIFICATION OF THE SCIENCES. 29 of account along with the others. As is of course the case also in the special branches of Physics, no demonstration that modified arrangements of simple particles accompany the qualitatively different phenomena can annul their actual differences of quality. Hence, even if matter as it must be for Mechanics were found to be everywhere ultimately homogeneous, this would not efface the division between Chemistry and Physics. With Comte we must add to the list of objective sciences that are fundamental and abstract the science of Life. For vital phenomena are distinguishable from chemical as those from physical phenomena by presenting a new problem of general form, and not merely particular empirical aggregations to be explained by combining and applying the orders of scientific truth already determined. The general problem of Biology is fixed by the nature of living organisms, which, as such, manifest what can only in fact be described as an " immanent end ". The parts of an organism act together in such a way that the union of their functions maintains, .against resistances that do not overpass certain limits, the continuous existence of an individualised whole. This con- sensus of functions clearly presents a higher problem than those of Chemistry and Physics, inasmuch as we get no hint from any special sense or combination of senses for the demarcation of it. The preceding sciences furnish the instruments for dealing with the problem of organic life in detail ; but that problem itself does not admit of a state- ment wholly resolving it into problems of Physics and Chemistry. And theories of the Evolution of Life cannot, of course, explain how there come to be living forms at all in distinction from the other objects in nature ; nor, on the positive side, how those forms are transmuted so as to become, when considered in relation to the general conception of an organism, more "organic". What they really set forth is certain conditions depending on the existence of many kinds of organisms together in space and time. Those conditions being known, and the generally teleological nature of an organism being given, the account of living forms on earth can be immensely simplified ; but the distinctive problem is not removed in this way any more than it is by the detailed study of physico-chemical processes in the particular organism. Of late, as it would be easy to show, philosophical Biology has become more and not less convinced of the irreducibility of its problem. The transition from Biology to Psychology is marked by the introduction of a new method. To observation and
