Physical object

“ Accordingly when we know all about the physical object, we thereby know its component sense-objects. But a physical object is a condition for the occurrence of sense-objects other than those which are its components. For example, the atmosphere causes the events which are its situations to be active conditioning events in the transmission of sound. A mirror which is itself a physical object is an active condition for the situation of a patch of colour behind it, due to the reflection of light in it. ”

“ Hence, if we remember that the ultimate object of all physical science is the successful formulation of such practical rules for action, we can see that it is a logical consequence of the character of the interests which dominate our scientific descriptions, that the physical sciences should adopt a rigidly mechanical view of the physical order. ”

“ The practical study of the physical sciences, being itself the most cardinal instance of inductive reasoning, will eminently conduce to the same object, and will supply to the Native mind, as it were, that fibre and sinew, that solid strength, which it so much needs. ”

“ We must answer in the negative. The objects of the natural sciences of the physical world arc of a material and spatial nature. A physical body has weight, occupies a certain portion of space, so has the molecule, the atom. ”

“ Now the state, including the shape or form, of a portion of matter, is the resultant of a number of forces, which represent or symbolise the manifestations of various kinds of energy; and it is obvious, accordingly, that a great part of physical science must be understood or taken for granted as the necessary preliminary to the discussion on which we are engaged. ”

“ And the whole circle of the Physical Sciences, or Physical Science in its widest extent, confines itself to explaining the appearances of the material world by the properties of matter, and to reducing what is complex and manifold to the operation of a few simple but all-pervading laws. ”

“ That the forms of natural bodies may depend upon different arrangements of the same particles of matter, has been a favourite hypothesis, advanced in the earliest era of physical research, and often supported by the reasonings of the ablest philosophers. ”

“ Physics, it is plain, tells us something about some of the constituents of the actual world; what these constituents are may be doubtful, but it is they that are to be called physical, whatever their nature may prove to be. ”

“ The position which I seek to establish in this essay is, that the various imponderable agencies, or the affections of matter which constitute the main objects of experimental physics, viz., heat, light, electricity, magnetism, chemical affinity, and motion, are all correlative, or have a reciprocal dependence;—that neither, taken abstractedly, can be said to be the essential or proximate cause of the others ”

“ The matter that surrounds us is divided into two great classes, living and dead; the latter is governed by physical laws, such as attraction, gravitation, chemical affinity; and it exhibits physical properties, such as cohesion, elasticity, divisibility, &c. Living matter also exhibits these properties, and is subject, in great measure, to physical laws. ”

“ Every motion which the accurate search of the experimentalist has traced, every principle or power which the physicist has discovered, every combination which the chemist has detected, every form which the naturalist has recorded, involves reflections of an exalting character, which constitute the elements of the highest poetry. The philosophy of physical science is a grand epic, the record of natural science a great didactic poem. ”

“ On the remaining pages of this paper I desire to direct attention to some of the facts connected with the main subject of my present inquiry—the concept force.
Physical forces are distributed by modern science into two classes, molecular and molar forces. Molecular forces are those which determine the internal changes of a body, while molar forces cause the motion of the entire mass. ”

“ The second class of powers embraces those which we can account for by the universally-known laws of physics. Among these I reckon the mechanism of motion, and the chemistry of the human body, the source of vegetable life. Vegetation, then, and animal mechanism, thoroughly mingled, form the proper physical life of the human body. ”

“ To take a definite example, one moreover which interests us most nearly, we may say that the nervous system, a material mass presenting certain qualities of colour, resistance, cohesion, etc., may well possess unperceived physical properties, but physical properties only. ”

“ If the properties of such a system of bodies are found to correspond to those of gases, an important physical analogy will be established, which may lead to more accurate knowledge of the properties of matter. ”

“ The same distinction could very easily be shown to be the foundation of every other science. All the physical sciences have this in common, that they are researches into what is real as distinguished from what is apparent, that is, from what lies exposed and obvious on the very surface of things. ”

“ In this imperfect sketch of the increased resources, and the present attitude of the physical sciences, I have not aimed to speak as an advocate, much less to sit as a judge. The great problem of the day is, how to subject all physical phenomena to dynamical laws. ”

“ B, C, D Physical Sciences.—Matter, force, motion and their applications are assumed to precede life and mind, and for that reason the material side of science, with its applications, has been selected as a foundation main class on which to construct the system. ”

“ It does not, of course, follow that all the sciences which deal in any way with the events of the physical order can as a matter of fact carry out this mechanical view of their objects with equal success. ”

“ Having now defined the use of the term force, and shown that forces are correlated which are convertible 44and mutually dependent, we go on to study the evidences of such correlation among the motions of inorganic nature usually called physical forces; and to ask what proof science can furnish us that mechanical motion, heat, light, and electricity are thus mutually convertible. ”

“ We are compelled to reserve our limited space for those branches of science which we are enabled to connect with the great natural operations constantly going on around us. Many of these more abstruse results will, however, receive some incidental notice when we come to examine the operation of the combined physical forces on matter. ”

“ Now, if we examine the real nature of those two important properties of life, we find that we can trace them, like all physiological functions, to physical and chemical causes, to the properties and the phenomena of motion of those substances of which the bodies of animals and plants consist. ”

“ Speculative or theoretical natural philosophy has to deal with natural substances and qualities, and is subdivided into physics and metaphysics. Physics inquires into the efficient and material causes of things; metaphysics, into the formal and final causes. The principal objects of physics are concrete substances, or abstract though physical qualities. ”

“ The principal impulse by which I was directed was the earnest endeavor to comprehend the phenomena of physical objects in their general connection, and to represent nature as one great whole, moved and animated by internal forces. My intercourse with highly-gifted men early led me to discover that, without an earnest striving to attain to a knowledge of special branches of study, all attempts to give a grand and general view of the universe would be nothing more than a vain illusion. ”

“ We deal with a compound or two-sided phenomenon—mental on one side, physical on the other; there is a definite correspondence in degree, although a difference of nature, between the two sides; and the physical side is itself in full correlation with the recognized physical forces of the world. ”

“ All the physical sciences have need of some definite material (ὕλη) because they are always concerned with noses, eyes, flesh, bones, animals, plants, roots, bark, in short with material things, subject to movement. ”

“ It will now be evident that in all chemical phenomena we have the combined exercise of the great physical forces, and evidences of some powers which are, as yet, shrouded in the mystery of our ignorance. ”

“ By it we find that the air has weight and pressure, color, density, elasticity, compressibility, and some other properties with which we shall endeavor to make the young reader acquainted by many pleasing experiments, earnestly impressing upon him to lose no opportunity of making physical science his study. ”

“ This appears to be the proper place for correcting an error too prevalent, relative to the formation of crystals, the development of cells, and the yet more fatal falsehood of referring the great phenomena of Life to any of the physical forces with which we are acquainted. ”

“ In the present Book we shall discuss some of the leading characteristics which everyday thought and scientific thought respectively assign to the physical order, and shall ask how these characteristics compare with those we have seen ground to ascribe to Reality, i.e. we shall attempt to form a theory of the place of physical existence in the whole system of Reality. ”

“ Physics treats of substances which move as masses, or which vibrate and rotate as molecules, without undergoing any appreciable change of structural integrity;5 they show changes of position and state, without corresponding changes in their elements. ”

“ One of the urgent needs of modern physical science is a thorough investigation of the nature, methods, and aids of scientific cognition, and thus of the nature of its real limits, chiefly in the light of the teachings of comparative philology and comparative psychology. ”

“ Hence bodies may be discovered, which,—from the imperfections of science,—resisting our means of analysis, must, for a time, be regarded as new elements, whereas they are possibly only altered states of the same substance. ”

“ Why the concurrence of every favorable condition is requisite for success in such inquiries may be readily comprehended. The object in view is to discern, singly, sparkling points, small as the point of a needle, and close as the particles of a handful of sand; so that it needs but the smallest unsteadiness in the air, or imperfection in the shape of the reflecting surface, to scatter the light of each point, to merge them into each other, and present them as one mass. ”

“ Under the head of physics we have the theory of the elements, of sound, heat and cohesion, and finally of chemical affinity—presenting the phenomena of material change and interchange in a series of special forces which generate the variety of the life of nature. ”

“ The principle is in some respects like what is called induction in physical science, which denotes the tendency of a body, which is in any particular magnetic or electric condition, to produce the same condition, and the same direction of polarity, in any similar body placed near it. ”

“ Every condition of organised forms is due to the external excitation of light and heat, and in the chemical changes which take place, an equivalent of these principles, or powers—it signifies but little according to which view we may regard them—is absorbed, and retained as essential to the condition of the matter formed. ”

“ The term physical is further employed to denote certain "affections of matter"—that is, mechanical effects which are the result of the action of force upon matter. It is true we often speak of "physical forces," as though force were an essential attribute of matter. ”

“ For example, the physical sciences deal only with those universal phenomena produced by physical forces; chemistry, in addition to these, deals also with a higher but more limited and special group of phenomena, determined by a peculiar force—chemical affinity; biology, in addition to all the preceding, deals also with a still higher and far more limited and special group of phenomena produced by a still more characteristic force—life. ”

“ The physical philosopher has it for his business to trace clouds to the laws of evaporation and condensation; to determine the magnitude and mode of action of the forces of cohesion and crystallization by which the materials of the earth are made solid and firm. ”

“ Thus physical quantities are aggregates of physical vibrations, and physical vibrations are the expression among the abstractions of physical science of the fundamental principle of æsthetic experience. ”

“ Just so far as we can recognize the ordinary modes of operation of the common forces of nature,—gravity, cohesion, elasticity, transudation, chemical action, and the rest,—we see the so-called vital acts in the light of a larger range of known facts and familiar analogies. ”

“ The Abstractive Method of Forming a Physical Theory, Distinguished from the Hypothetical Method. Two methods of framing a physical theory may be distinguished, characterized chiefly by the manner in which classes of phenomena are defined. ”

“ We cannot, for example, isolate a single domain of science in a particular country and at a particular time—say, [ 56 ] mechanics in England in the eighteenth century—and hope to make of it a thoroughly complete object of study. ”

“ We clearly conceive the manner how, and the conditions by which, motility, this most prominent vital manifestation, constitutes an inherent property of the living substance. Do we as yet comprehend in the same way the intimate modes of activity which constitute the properties appertaining to inorganic substances? Is any kind of those peculiar motions which form the scientific essence of the various forces of inorganic Nature so strictly and deeply intelligible as has now become that specific motion which forms the scientific essence of the force of life? ”

“ We want to see how, in some cases at least, the forms of living things, and of the parts of living things, can be explained by physical con­si­de­ra­tions, and to realise that, in general, no organic forms exist save such as are in conformity with ordinary physical laws. ”