No two atoms of spirit or any other matter can occupy two or more places at the same time. We have never known of a circumstance of the spirit of man residing in the body and out of it at the same time. No particles of light, odour, heat, electricity, can occupy two places at once. These substances can only be extensively diffused by being extensive in quantity. The particles of light which enter the right eye are not the same which enter the left eye. Though their qualities may be exactly alike, yet they are separate individual substance, as much so as if they were millions of miles asunder. The same is true of the atoms of spirit and all other substances.
OF THE ESSENCE OF SUBSTANCES.
Philosophers of modern times have asserted that we know nothing of the essence of bodies. It is affirmed that all that can be known of mind or matter, are merely its properties. Dr. Abercrombie, says, "We talk, indeed, about matter, and we talk about mind; we speculate concerning materiality and immateriality, until we argue ourselves into a kind of belief that we really understand something of the subject. The truth is, we understand nothing. Matter and mind are known to us by certain properties: but in regard to both it is entirely out of the reach of our faculties to advance a single step beyond the facts which are before us. Whether in their substratum or ultimate essence, they are the same, or whether they are different we know not, and never can know in our present state of being." (Abercrombie on the Intellectual Powers. Part I. Sec. I.)
There are many truths which we ascertain by reflection, independently in a great measure of our senses. We are assured and know in our own minds that duration must be endless, and that space must be boundless, not because we have learned these truths directly through the medium of our senses, or have been able to demonstrate them by any process of reasoning. In the same way we know concerning the essence of bodies. Instead of being entirely ignorant on the subject, as modern philosophers assert, it is directly the opposite; we know the essence of all substances. Solidity is the only essence in existence. Although the ultimate atoms of matter cannot come under the cognizance of our senses, and we cannot demonstrate their solidity by any process of reasoning, yet we are none the less assured of their solidity. We believe that they are solid because it is impossible for us to believe otherwise. We are as certain that the ultimate atoms of all substances are solid, as we are that they exist. What we mean by solidity is, that all substances completely fill a certain amount of space, and that it is impossible for them ever to fill a greater or less amount of space.
The amount of absolute space occupied by any substance is constant, that is the elementary atoms cannot be increased or decreased in magnitude in the least degree. Particles may be divided, but their respective parts occupy the same amount of space when separated as when united. Condensation or expansion is not a property of the ultimate atoms of bodies, but merely the relation which these atoms sustain to each other. When a collection of atoms called body are forced into a closer connexion with each other, the body is said to be condensed. When their relative distances are increased the body is expanded. The maximum of density excludes all pores. In such a condition the space is wholly occupied—any further condensation is absolutely impossible. A bar of iron varies its dimensions with its temperature, while the atoms of which the bar consists remain unchangeable in size. The pores of the iron increase in the same proportion as the bar increases, and diminish as the bar diminishes. Solidity is universally supposed to be a property of atoms, but this is an error. Solidity is not a property, but only another name for the essence. A property must be a property of something; but solidity is not a property of anything—it is the essence itself—the thing that exists, aside from all properties and powers. If we suppose solidity to be a property, then it is evident that there must be a distinction between atoms as possessors, and solidity as the thing or property possessed; but we find it impossible to conceive of atoms separate and apart from solidity. Deprive atoms of solidity, and they are deprived not of a property, but of existence itself, and nothing remains. Solidity is associated with existence, and we cannot conceive of the one independently of the other. Solidity, then, is the essence to which all qualities belong—taste, smell, colour, weight, &c., are the affections of solids. Every feeling or thought is the feeling or thought of solids. All the powers of the universe, from the almighty powers of Jehovah down to the most feeble powers that operate, are the powers of solid atoms. We can conceive of solid atoms existing without powers, but we cannot conceive of atoms existing without solidity; therefore the very essence of all substance is solidity. Love, joy, and all other affections are only the different states of this essence.
When the essence or solidity of substance is considered by itself, independently of its powers, there cannot possibly be any difference in atoms only in their magnitude and form. The essence of all substance is precisely alike when the essence alone is considered. Substances can only differ in their magnitude, form, and susceptibilities, but not in their essences, for they are and must be alike.
THE IMMATERIALISTS ONLY POSSIBLE ARGUMENT REFUTED.
The only possible argument which the immaterialist pretends to bring forward in support of the inextension and indivisibility of a thinking substance, and consequently of its immateriality—is founded on the self-consciousness of such substance.
A thinking substance is conscious of its own individual unity: it is conscious that itself is not many beings, but one. Mankind universally feel their own individual unity when each contemplates himself. Each one is certain that it is the same being that rejoiced yesterday who remembers to-day—that all past and present affections are the affections of one being, and not of many. The absolute oneness of a thinking being is supposed to be inconsistent with a plurality of parts. To avoid this supposed inconsistency the immaterialist assumes that such a substance is without parts.
Dr. Brown says "that the very notion of plurality and division is as inconsistent with the notion of self as the notions of existence and nonexistence." (Brown's Philosophy of the Human Mind. Lecture XCVI.) That by the term "plurality," he means the plurality of parts, as well as a plurality of atoms,—is very evident from the whole tenor of his reasoning. If the materialist, as Dr. Brown again says, "assert thought to be the affection of a single particle, a monade; he must remember that if what he chooses to term a single particle, be a particle or matter, it too must still admit of division; it must have a top and bottom, a right side and a left; it must, as it is demonstrable in geometry, admit of being cut in different points, by an infinite number of straight lines; and all the difficulty of the composition of thought, therefore, remains precisely as before." "If it be supposed," continues he, "so completely divested of all the qualities of matter, as not to be extended, nor consequently divisible, it is then mind which is asserted under another name, and every thing which is at all important in the controversy is conceded." (Brown's Philosophy of the Human Mind. Lecture XCVI.)