existence thought under relation. Relation may be understood to contain all the categories and forms of positive thought. We should not, however, think it as a law of things, but simply as a law of thought; for we find that there are contradictory opposites, one of which, by the rule of Excluded Middle, must be true, but neither of which can be positively thought, as possible. Thinking, under this condition, is synthetic. The condition of Relativity is brought to bear under three principal relations: the first springs from the subject of knowledge the mind thinking, the relation of knowledge; the second and third from the object of knowledge-the thing thought about, the relations of Existence.

1. The relations of knowledge are those arising from the reciprocal dependence of the subject and of the object of thought, self and notself-subjective and objective. Every thing that comes into consciousness is thought by us, either as belonging to the mental self exclusively, or as belonging to the not-self exclusively, or as belonging partly to both.

2. The relations of Existence arising from the object of knowledge are twofold; as the relation is either Intrinsic or Extrinsic. As the relation of Existence is Intrinsic, it is that of Substance and Quality. It may be called qualitative. But, as the relation of Existence is Extrinsic, it is threefold; and as formed by three kinds of quantity, it may be called quantitative. It is realised in or by: (1) Protensive quantity, or time; (2) Extensive quantity, Extension or Space; (3) Intensive quantity, or degree.

3. Time, or protensive quantity, called also Duration, is a necessary condition of thought; and it may be considered both in itself and in the things which it contains.

Considered in itself, Time is positively inconceivable, if we attempt to construe it in thought; on the one side, as absolutely commencing or absolutely terminating, or on the other, as infinite or eternal. It is positively conceivable, if conceived as an indefinite past, present, or future; and as an indeterminate mean between the two unthinkable extremes of an absolute least and an infinite divisibility for thus it is relative.

Things in Time are either coinclusive or coexclusive. Things coinclusive, if of the same time, are identical, apparently and in thought; if of different times, as causes and effect, they appear as different, but are thought as identical. Things coexclusive are mutually either prior and posterior, or contemporaneous.

The impossibility we experience of thinking as non-existent, nonexistent, consequently, in time, aught which we have conceived as existent, this impossibility affords the principle of Causality, which will be subsequently explained.

Time applies to both Substance and Quantity; and includes the other quantities, Space and Degree.

4. Space, extension or extensive quantity, is likewise a necessary condition of thought; and may also be considered, both in itself and in the things which it contains.

Considered in itself, Space is positively inconceivable as a whole, either infinitely unbounded, or absolutely bounded; as a part, either infinitely divisible, or absolutely indivisible. Space is positively conceivable, as a mean between these extremes; that is, we can think it either as an indefinite whole, or as an indefinite part. For thus it is relative.33 So much touching the foundation of the philosophy of the Conditioned.

"34

He enounced the Law of the Conditioned thus :-" All positive thought lies between two extremes, neither of which we can conceive as possible, and yet, as mutually contradictory, the one or the other must necessarily be true." We have already seen that we cannot think past time as beginning to be; on the other hand, we cannot conceive it going backwards without limit-eternity baffles our imagination. But time either had a beginning or it had not. So of space, we are unable to conceive space as finite or bounded; we are equally powerless to realise in thought an idea of infinite space. "You may launch out in thought beyond the solar walk, you may traverse in fancy over the universe of matter, and rise from sphere to sphere in the regions of empty space, until imagination sinks exhausted ;-with all this what have you done? You have never got beyond the finite, you have attained at best only to the indefinite, and the indefinite, however expanded, is still always the finite. The infinite is infinitely incomprehensible." Thus the conceivable or the thinkable "lies always between two inconceivable extremes, as illustrated by every other relation of thought." 35

The chief applications of the Law of the Conditioned are to the

33 Discussions, pp. 577-582.

34 Discussions, p. 591; also Reid's Works, p. 911. Hamilton states the Law of the Conditioned repeatedly in his different writings; and some of its positions are stated at greatest length in the second volume of his Lectures.

35 Discussions, p. 591; Lectures, Vol. II., pp. 366-372.

:

principles of substance and causality and taking substance first, which he has not treated with much detail. We cannot think a quality existing entirely in or of itself. We are constrained to think it as inhering in some substance; but this substance is only conceived by us the unapparent the inconceivable correlative of certain appearing qualities. If we attempt to think it positively, we only think it by transforming it into a quality or bundle of qualities, which again we refer to an unknown substance, now supposed for their incognisable basis. Thus, everything may be conceived as the quality, or as the substance of something else; but absolute substance and absolute quality are both inconceivable.86

The phenomenon of causality is the Law of the Conditioned applied to a thing thought as existing in time. We cannot know, nor think a thing, except under the attribute of existence, and existing in time; and we cannot know or think a thing to exist in time, and think it absolutely to commence. This imposes on us the judgment of causality. An object is given to us by our perceptive faculties, as given, we cannot but think it existent, and existent in time; but to say this, is to say, that we are unable to think it nonexistent, to annihilate it in thought, and this we cannot do; for once thinking it to exist, we cannot think it not to exist. This will be admitted of the present, but probably denied of the past and future, under the belief that we can think creation or annihilation. Matter or objects may change their forms in innumerable ways; but we cannot conceive that there can be an atom absolutely added to, or taken away from, existence as a whole. Let us try it :

"We are able to conceive the creation of a world; this indeed as easily as the creation of an atom. But what is our thought of creation? It is not a thought of the mere springing of nothing into something. On the contrary creation is conceived, and is by us conceivable, only as the evolution of existence from possibility into actuality, by the fiat of the Deity. Let us place ourselves in imagination at its very crisis. Now, can we construe it to thought, that the moment after the universe flashed into material reality, into manifest being, that there was a larger complement of existence in the universe and its author together, than the moment before there subsisted in the Deity alone? This we are unable to imagine. And what is true of our concept of creation, holds of our concept of

annihilation. We can think no real annihilation, no absolute sinking of something into nothing. But, as creation is cogitable by us, only as a putting forth of divine power, so is annihilation by us only conceivable as a withdrawal of that same power. In short, it is impossible for the human mind to think what it thinks existent, lapsing into non-existence, either in time past or in time future."37 He thinks that his theory of causality is preferable to others, because to explain the phenomenon of the causal judgment, it postulates no new or express principle, not even a positive power; while it shows that the phenomenon is only one of a class, it assigns as their common cause, only a negative impotence. He also thinks that it affords a philosophical defence of the freedom of the will. He points out the inconsistencies and contradictions of his predecessors; but he admits that speculatively we are unable to understand how moral liberty is possible in man. But practically, our consciousness of the moral law gives a decisive preponderance to the doctrine of freedom over the doctrine of fate. We are free in act, if we are accountable for our actions. That the philosophy of the Conditioned has a real foundation in the human mind, appears to be evident, when considered in its relation to the universe. The necessities of its capacities and faculties of knowledge. their limits and imperfection, as well as the actual position in which man finds himself in the universe of nature, all plainly indicate that his powers of knowledge are anything rather than absolute and infinite. This much may be averred; still, it is open to anyone to question, if Hamilton's applications of his own theory were in all points the most legitimate. I will now proceed to his logic.

He viewed Logic as a formal science, and divided it into pure and modified. In his lectures on this subject, he proceeds on a definite and interesting style of exposition; he first states the leading doctrines in separate paragraphs, and then in a running commentary explains and illustrates them. The first paragraph is this:-" A system of logical instruction consists of two parts-(1) Of an introduction to the science; (2) of a body of doctrine constituting the science itself." These he discussed in their order: the introduction to logic should afford answers to the five following questions: What is logic? what is its value? what are its divisions? what is its history? what are the best books on the subject. These questions

7 Discussions, pp. 591-593; Lectures, Vol. II. pp. 400-406.

are treated in a concise and animated style; and the answer to the first one is given in his definition of logic, which is this:-" Logic is the Science of Thought as thought." But he says that this definition cannot be understood without a clear exposition of its several parts, which he proceeds to present.

What he meant by "the laws of thought as thought," is thus explained the term thought is used in two significations, in a wider, and in a narrower and stricter sense, and it is with thought in the latter sense-thought proper, that logic is concerned. "All thought is a comparison, a recognition of similarity or difference; a conjunction or disjunction, in other words, a synthesis or analysis of its objects. But thought simply is still too undetermined; the proper object of logic is something still more definite; it is not thought in general, but thought considered merely as thought, of which this science takes cognisance. What is meant by

thought as thought? It is the recognition of a thing as coming under a concept; in other words, the marking an object by an attribute or attributes previously known as common to sundry objects, and to which we have accordingly given a general name. Logic is properly conversant with the form of thought to the exclusion of the matter.

"But the limitation of the object-matter of logic to the form of thought, is not yet enough to determine its province from that of other mental sciences; for psychology is, in like manner, among other mental phenomena, conversant about the phenomena of formal thought. A still further limitation is, therefore, requisite; and this is given in saying, that logic is the science not merely of thought as thought, but the laws of thought as thought, . or the science of the formal laws of thought, or the science of the laws of the form of thought; these being three various expressions of the same thing."38

He gives further explanations, of which this is one :-" Abstract logic considers the laws of thought as potentially applicable to the objects of all arts and sciences, but as not actually applicable to those of any; concrete logic considers these laws in their actual and immediate application to the object-matter of this or that particular art or science. The former of these is one, and alone belongs to philosophy, whereas the latter is as multiform as the arts and sciences to which it is relative." 39

38 Lectures, Vol. III., pp. 3-26.

39 Vol. III., p. 53.