Matter and energy

The behaviour of matter and energy represents one aspect only of human knowledge, which is generally known by the name of physical science. It seems well to state at the outset that, throughout these pages, when the term science is employed it refers solely to this one branch. Physical science enjoys the distinction of being the most fundamental of the experimental sciences, and its laws are obeyed universally, so far as is known, not merely by inanimate things, but also by living organisms, in their minutest parts, as single individuals, and also as whole communities. It results from this that, however, complicated a series of phenomena may be and however many other sciences may enter into its complete presentation, the purely physical aspect, or the application of the known laws of matter and energy, can always be legitimately separated from the other aspects.

This aspect comes first, not necessarily in relative importance, but in the order of the scientific definition of the phenomena and of the problems it presents for a solution. A great simplification thereby results, which is too often neglected.

Complete ignorance of these laws is, nowadays, rare, for they enter into the general common sense of the age, and any flagrant violation of them is quickly exposed. But they neglect to give precedence to the purely physical aspect of the complicated occurrences and events of human experience in their orderly presentation has led to much-confused history and a general lack of clearness as to the precise terms with Nature on which the race exists on this planet. There is a special branch of study known as physical geography, but the need for a similar branch of physical history does not appear to have been widely felt.

The laws expressing the relations between energy and matter are, however, not solely of importance in pure science. They necessarily come first in order, in the fundamental sense described, in the whole record of human experience, and they control, in the last resort, the rise or fall of political systems, the freedom or bondage of nations, the movements of commerce and industry, the origin of wealth and poverty, and the general physical welfare of the race.

If this has been too imperfectly recognized in the past, there is no excuse, now that these physical laws have become incorporated into everyday habits of thought, for neglecting to consider them first in questions relating to the future. It is an interesting and by no means hackneyed side of the subject to consider, so far as the operation of purely physical laws can teach, exactly what the future has in store for this world and the complicated civilisation that it contains. Is it a stable and permanent movement, or does it carry in itself, like the life of the individuals that comprise it, the seeds of its own inevitable decay?

Moreover, if, as will transpire when the nature of the controlling physical laws has been made clear, it is ephemeral and will decline the sooner the more rapid its development and the more glorious the zenith it attains, what alteration of the existing conditions would suffice to convert it into a physically stable and permanent movement?

On these great questions, rendered the more fascinating because of the disposition, since the development of the doctrine of evolution, to consider the fate and future of the individual as of little importance compared with the fate and future of the species, physical science in its later developments has much to say that is of general interest. The proverb counselling the cobbler to stick to his last is a good one; but since the province of physical science is the universe and all that moves therein, its right to be heard first, in order of presentation of the subject only, cannot be withstood. It may or may not assist in disclosing the fundamental bearings of any question, but anything it has to say will, in general, be definite and, in so far as the laws are perfectly known, incapable of being invalidated by any other considerations whatever. The laws may not be fully known and may give rise to false deductions, a case of which arose in the question of the duration of geological time.

In such a case, the discussion of the conflicting evidence can only result in the advance of knowledge. Physical science, by reason of the universality of its laws, has something to say on almost every subject. It need only be stated once for all, that although the purely physical side can be considered separately, it does not render other points of view less necessary, though, of course, it is only with the physical point of view that the present volume is concerned.

To adopt for the moment the language of Spencer's Classification of the Sciences, referred to in the Introductory volume of this Series (p. 89), physical science supplies subject- matter for every actual occurrence in the universe, but none of the truths outside of physical science can help in the solution of physical problems.

The recognition of the fundamental physical conditions which control the destinies of a race too often occurs too late in its development to be of service. History throws some strange sidelights on this blindness to the obvious.

Matter and energy - PDF book by Frederick Soddy