realize values. He might suffer delay- but not deprivation. . . . The proposed legislation . . . would be within the legislative power and would not operate as a taking of private property for which compensation must be made."

The Court of Errors and Appeals of New Jersey has adopted a similar view, which has recently been sustained by the Supreme Court of the United States. In delivering the opinion of the court on April 6, 1908, Mr. Justice Holmes said: "The state as quasi-sovereign and representative of the interests of the public has a standing in court to protect the atmosphere, the water and the forests within its territory, irrespective of the assent or dissent of the private owners of the land most immediately concerned. . . . It appears to us that few public interests are more obvious, indisputable and independent of particular theory than the interest of the public of a state to maintain the rivers that are wholly within it substantially undiminished, except by such drafts upon them as the guardian of the public welfare, may permit for the purpose of turning them to a more perfect use. This public interest is omnipresent wherever there is a state, and grows more pressing as population grows. We are of opinion, further, that the constitutional power of the state to insist that its natural advantages shall remain unimpaired by its citizens is not dependent upon any nice estimate of the extent of present use or speculation as to future needs. The legal conception of the necessary is likely to be confined to somewhat rudimentary wants, and there are benefits from a great river that might escape a lawyer's view. But the state is not required to submit even to an æsthetic analysis. Any analysis may be inadequate. It finds itself in possession of what all admit to be a great public good, and what it has it may keep and give no one a reason for its will."

These decisions reach the root of the idea of conservation of our resources in the interests of our people.

Finally, let us remember that the conservation of our

natural resources, though the gravest problem of to-day, is yet but part of another and greater problem to which this nation is not yet awake, but to which it will awake in time, and with which it must hereafter grapple if it is to live the problem of national efficiency, the patriotic duty of insuring the safety and continuance of the nation. When the people of the United States consciously undertake to raise themselves as citizens, and the nation and the states in their several spheres, to the highest pitch of excellence in private, state and national life, and to do this because it is the first of all the duties of true patriotism, then and not till then the future of this nation in quality and in time will be assured.

HUXLEY1

PAUL ELMER MORE

In a world that is governed by phrases we cannot too often recur to the familiar saying of Hobbes, that "words are wise men's counters, they do but reckon by them; but they are the money of fools"; and so to-day, when the real achievements of science have thrown a kind of halo about the word and made it in the general mind synonymous with truth, the first duty of any one who would think honestly is to reach a clear definition of what he means when he utters the sanctified syllables. In this particular case the duty and difficulty are the greater because the word conveys three quite different meanings which have correspondingly different values. Positive science is one thing, but hypothetical science is another thing, and philosophical science is still another; yet on the popular tongue, nay, even in the writings of those who pretend to extreme precision, these distinctions are often forgotten, to the utter confusion of ideas.

By positive science I mean the observation and classification of facts and the discovery of those constant sequences in phenomena which can be expressed in mathematical formula or in the generalized language of law; I mean that procedure which Huxley had in mind when he said that science is "nothing but trained and organized common sense, differing from the latter only as a veteran may differ from a raw recruit: and its methods differ from those of common sense only so far as the guardsman's cut and thrust differ from the manner in which a savage wields his club." Now for such a procedure no one can feel anything but the highest respect

1 From The Drift of Romanticism; copyright. Reprinted by permission of the author and of Houghton Mifflin Company.

respect which in the lay mind may well mount to admiration and even to awe. He has but a poor imagination who cannot be stirred to wonder before the triumphs over material forces gained by methods of which he can confess only humble ignorance; and beyond these visible achievements lies a whole region of intellectual activity open to the man of science, but closed and forever foreign to the investigator in other kinds of ideas. I am bound to insist on the fact that I have no foolish desire to belittle the honors of science in its practical applications, and that I can in a way estimate its rewards as an abstract study, however far the full fruition of the scientific life may lie beyond my reach.

Positive science, thus defined as that trained observation which brings the vision of order out of disorder, system out of chaos, law out of chance, might seem splendid enough in theory and useful enough in practice to satisfy the most exorbitant ambition. But it must be remembered that a law of science, however wide its scope, does not go beyond a statement of the relation of observed facts and tells us not a word of what lies behind this relationship or of the cause of these facts. Now the mind of man is so constituted that this ignorance of causes is to it a constant source of irritation; we are almost resistlessly tempted to pass beyond the mere statement of law to erecting a theory of the reality that underlies the law. Such a theory is an hypothesis, and such activity of the mind is hypothetical science as distinguished from positive science. But we must distinguish further. The word hypothesis is used, by the man of science as well as by the layman, in two quite different senses. On the one hand, it may mean the attempt to express in language borrowed from our sensuous experience the nature of a cause or reality which transcends such experience. Thus the luminiferous ether is properly an hypothesis: by its very definition it transcends the reach of our perceptive faculties; we cannot see it, or feel it in any way; yet it is, or was, assumed to

exist as the cause of known phenomena and its properties were given in terms of density, elasticity, etc., which are appropriate to material things which we can see and feel. On the other hand, the word hypothesis is often taken to signify merely a scientific law which belongs to the realm of positive science, but which is still to be established. Confusion would be avoided if we employed the term scientific conjecture for this second, and proper, procedure, and confined the use of the term hypothesis to the former, and as I think improper, procedure. To make clear these distinctions let me give an illustration or two. The formula of gravitation merely states the regularity of a certain group of known phenomena from the motion of a falling apple to the motion of the planets about the sun. When this formula first dawned on the mind of Newton, it was a scientific conjecture; when it was tested and proved to conform to facts, it became an accepted scientific law. Both conjecture and accepted law are strictly within the field of positive science. But if Newton, not content with generalizing the phenomena of gravitation in the form of a law, had undertaken to theorize on the absolute nature of the attraction which caused the phenomena of gravitation,' he would have passed from the sphere of positive science to that of hypothetical science. So when Darwin, by systematizing the vast body of observations in biology and geology, showed that plants and animals develop in time and with the changes of the earth from the simplest forms of animate existence to the most complex forms now seen, and thus gave precision to the law of evolution, he was working in the field of positive science: he changed what had been a conjectured law to a generally accepted law. But when he went a step further and undertook to explain the cause of this evolution by the theory of natural selection or the survival of the fit, he passed from positive to hypothetical science.

1 On this point compare Berkeley, Siris, §§ 245-250.