Scientific hypothesis

“ If we choose to define positive science as the systematic establishment of the special laws of connection between facts, we may say that over and above the scientific problem of the systematisation of facts there is the further philosophical problem of their interpretation. ”

“ If we assume that there is a real world of things in themselves, constituting the underlying cause of our sense experience, the point we wish to ascertain is whether scientific procedure can throw any light on its nature. ”

“ Mathematics and physics and chemistry and biology and psychology, not to say also the social sciences, all depend upon the far-seeing mystical visions of the mind, if not of the eye, upon the subtle, logical constructions which their would-be scientific specialism, their desire to know all things narrowly, forces upon them. ”

“ The special science, because special or partial and because at the same time courting scientific character or validity, that is, conformity with reality, must be relative, formal, abstract, artificial, unreal, but also for exactly the same reason it must contrive to admit to its conceptions other view-points than its own. ”

“ To learn a proposition by experience, and to see it to be necessarily true, are two altogether different processes of thought.
2. But it may be said, that we do learn by means of observation and experience many universal truths; indeed, all the general truths of which science consists. Is not the doctrine of universal gravitation learnt by experience? Are not the laws of motion, the properties of light, the general principles of chemistry, so learnt? How, with these examples before us, can we say that experience teaches no universal truths? ”

“ In the first place, do these supposed causes of the phenomena exist in nature? Is it the fact that, in nature, these properties of organic matter–atavism and variability–and those phenomena which we have called the conditions of existence,–is it true that they exist? Well, of course, if they do not exist, all that I have told you in the last three or four lectures must be incorrect, because I have been attempting to prove that they do exist, and I take it that there is abundant evidence that they do exist; so far, therefore, the hypothesis does not break down. ”

“ And the empirical circumstances are such that we have every reason to believe the hypothesis to be true. We are as sure of it as of the best founded physical laws that science has discovered.
As a matter of fact, we have already pointed out that there are certain regularities in the world which experience shows to be entirely independent of what happens to human beings on the earth. ”

“ This scientific conception of causation has been developed and rendered definite by the investigations of those physical sciences that can avail themselves of exact experiments and mathematical calculation; and it is there, in Chemistry and Physics, that it is most at home. The conception can indeed be carried into the Biological and Social Sciences, even in its quantitative form, by making the proper allowances. For the limbs of animals are levers, and act upon mechanical principles ”

“ There are those who reason and dogmatize as though nature were synonymous with matter, or as though spirit, if there be such an essence, must be conceived and explained after the principles and analogies of matter;—others assume that a science of scientific method can be nothing better than the vimist or moonshine which they vilify by the name of metaphysics. ”

“ And the natural drift of the human mind is ever towards this abstract conception--this one all-encompassing law of the universe. It steadily speculates in this direction, and some of the highest triumphs of our age, in physical as well as metaphysical science, are measurably due to this tendency. The scientific mind is not confined wholly to experimental research. ”

“ All these spheres of science, from mathematics to psychology, dovetail into one another, as terms like bio-chemistry, psycho-physics and physical chemistry indicate.
It might be urged that the results embodied in the special sciences do not embody all of nature; that there is mind and consciousness, that there are emotions, values in quality, religious instincts, and so on. But here it should be remembered that whatever transcends the sphere of the special sciences transcends it precisely because it is vague and only dimly apprehended. ”

“ In thus attempting to ascertain the general order of nature by ascertaining the particular order of the occurrence of each one of the phenomena of nature, the most scientific proceeding can be no more than an improved form of that which was primitively pursued by the human understanding, while undirected by science. ”

“ The fundamental propositions rest on a much broader basis of experiment than any of the beliefs which are held most strongly in every day life. Under these circumstances nobody should speak disparagingly of the validity of scientific knowledge — not even the scientist himself. ”

“ It is true, no fundamental objection can be raised to this method, as even modern natural science and medicine, despite the fact that their methods of investigation in a diagnostico-theoretical respect scarcely admit of material objections, can not do without hypothesis. But hypothesis is not always mere hypothesis. ”

“ But a disposition to such a judgment arises in a great measure from this, that the mathematical and mathematico-physical sciences have, in a great degree, determined men's views of the general nature and form of scientific truth; while Natural History has not yet had time or opportunity to exert its due influence upon the current habits of philosophizing. ”

“ Some fact is as yet little understood, or some law is unknown; we frame on the subject an hypothesis as accordant as possible with the whole of the data already possessed; and the science, being thus enabled to move forward freely, always ends by leading to new consequences capable of observation, which either confirm or refute, unequivocally, the first supposition. ”

“ The other consideration I have to put before you is that, whatever may be the results at which physical science as applied to man shall arrive, those results are inevitable—I mean that they arise out of the necessary progress of scientific thought as applied to man. ”

“ On this point even physicists agree. "Instead of regarding the proper object of physical science as a search after essential causes," says one of the best modern champions of scientific progress, "it ought to be, and must be, a search after facts and relations." [90] Hence, physical science deals with natural facts and their relations exclusively; the search after causes and essential principles constitutes the object of a higher science; and such a science is real philosophy, or metaphysics proper. ”

“ We are accustomed, as you are aware, when traveling into new ground to form first an hypothesis as an explanation of the facts known to us. Beginning with this hypothesis, we first reason out the consequences which must follow if the hypothesis should be the real explanation. We then proceed to test these consequences by experiment. We then reason out other necessary consequences of the hypothesis and proceed further with our tests. If the results of our tests confirm 54the hypothesis it presently becomes a theory and in course of time a law. ”

“ Has science any place for such theories? Why be a 'neo-vitalist,' or an 'evolutionist,' or an 'atomist,' or an 'Energetiker'? Why not say, plainly: "Such and such phenomena, thus and thus described, have been observed; such and such experiences are to be expected, since the hypotheses by the terms of which we are required to expect them have been verified too often to let us regard the agreement with experience as due merely to chance; so much then with reasonable assurance we know; all else is silence—or else is some matter to be tested by another experiment?" ”

“ Aims at a critical comparison of scientific methods of thought, with special reference to the relations between biology and the " exact sciences " of chemistry and physics.
"Interesting and valuable . . . original and striking . . . should be read and studied by all thinking men and women." — Education. ”

“ The interest in the formulation of general rules for practical interference with nature, again, necessarily dictates the form which our scientific descriptions will take, and is thus the source of those practical postulates of empirical science with which we have already made some acquaintance. 284It compels us to assume, in the first place, as an indispensable condition of success in our descriptions, that there are situations in the physical order which may be treated with sufficient accuracy for our practical purposes, as recurring identically ”

“ The hypothesis, in the next place, assumes no special cause, known or unknown, physical or hyperphysical, but accepts that which, by universal consent, is not only the cause of inorganic phenomena, but the invariable concomitant, if not the cause, of the phenomena of life. ”

“ What unites all things into a continuous, coherent, and systematic cosmos, into a scientific [107] whole, is first the fact that, whether phenomena in sense or phenomena in idea, they are all objects of thought; and next the fact that they all exhibit the universality of causation and the uniformity of nature. ”

“ By this deduction of all natural phenomena from an absolute hypothesis, our knowing is changed into a construction of Nature itself, that is, into a science of Nature à priori. If, therefore, such deduction itself is possible, a thing which can be proved only by the fact, then also a doctrine of Nature is possible as a science of Nature; a system of purely speculative physics is possible, which was the point to be proved. ”

“ On the other hand, psychology is beginning to return, as it were, in a spirit of thankfulness, the powerful stimulus which it received from physics.
The theories of physics which reduce all phenomena to the motion and equilibrium of smallest particles, the so-called molecular theories, have been gravely threatened by the progress of the theory of the senses and of space, and we may say that their days are numbered. ”

“ And when we fully recognize that a problem is being solved, we have only to gain some appreciation of its general nature and conditions, in order to reach some important, though limited, conclusions, which may fairly be called scientific, as to the meaning of the answer. These conclusions are not scientific in the sense of giving us quantitative and precise formulæ, but they may be so far scientific as to be certain and reliable. ”

“ They could no longer produce the manifestations contingent on their own finite and material senses, although said to originate with spirits.
Scientific results are based on a demonstrable Principle, explained in Science. Phenomena produced by belief are destitute of Principle and Science. ”

“ The advance of scientific knowledge—the astonishing discovery of the atom and the cell, and of the unsubstantially or unmateriality, so to speak, of matter itself, and of the elusiveness of energy and life, as indicated by the newer theories of the nature of the ether, and the acceptance of thought-transference as a physical or psychological fact—these and other remarkable scientific discoveries which are leading science to what is seemingly the borderline of a world beyond the cognizance of the bodily senses, have powerfully affected the rationalism and idealism of the present day. ”

“ Inductive truths are of two kinds, Laws of Phenomena, and Theories of Causes. It is necessary to begin in every science with the Laws of Phenomena; but it is impossible that we should be satisfied to stop short of a Theory of Causes. In Physical Astronomy, Physical Optics, Geology, and other sciences, we have instances showing that we can make a great advance in inquiries after true Theories of Causes. ”

“ It is necessary, before quitting the subject of hypotheses, to guard against the appearance of reflecting upon the scientific value of several branches of physical inquiry, which, though only in their infancy, I hold to be strictly inductive. ”

“ After this preliminary statement of the results of experimental investigation, we said, "Therefore, it is now regarded as a fundamental truth of physical science, and a fundamental law of Nature, that force, like matter, is never created or destroyed." The proposition is stated as an inference, as an induction from observations, as a result of experimental inquiry into the physical processes of Nature, and as a pure principle of science. ”

“ In the current language of the physicists, an hypothesis of this importance is called a theory, while the term hypothesis is restricted to suggestions which have little evidence in their favor. There is some justice in the contempt which clings to the word hypothesis. To think that we can strike out of our own minds a true preconception of how Nature acts, is a vain fancy. ”

“ We have seen that in other subjects the Fundamental Ideas on which science depended, and the Conceptions derived from these, were at first vague, obscure, and confused;—that by gradual steps, by a constant union of thought and observation, these conceptions become more and more clear, more and more definite;—and that when they approached complete distinctness and precision, there were made great positive discoveries into which these conceptions entered ”

“ When physical science is said to depend on the assumption that the course of nature is invariable, all that is meant is that the conclusions of physical science are not known as absolute truths: the truth of them is conditional on the uniformity of the course of nature; and all that the most conclusive observations and experiments can prove, is that the result arrived at will be true if, and as long as, the present laws of nature are valid. But this is all the assurance we require for the guidance of our conduct. ”