ocean swells up and manifests itself in the unending succession of its

waves.

IV. Rational intuition is necessary to interpret sense-perception.

Sensation reports correctly the peculiar impression of outward agents on each sense. But it is only by judgment in accordance with the principles of reason that we apprehend the reality signified by the impression on the sensorium. The senses show us the sky as a blue dome, the sun, moon and stars as moving in it, parallel rails converging as they recede; and always we resort to reason to interpret these presentations of sense and ascertain what the reality is which they bring before us. The ear gives us sound, the eye light and shade, the general sensorium heat; but it is thought, regulated by the principles of reason, which discloses the undulations which impinge on the ear and cause sound, and the molecular vibrations which cause light and heat. And it is thought, guided by the principles of reason, which carries knowledge to distances of space and time entirely beyond the observation of sense, and discovers that the facts known by sense are in the unity of a rational system.

Those who doubt the validity of rational intuition are wont to point in contrast with great satisfaction to the clearness and certainty of knowledge by sense-perception. But it is evident that without the aid of the rational intuition sense-perception could gain but a small part of our knowledge of the physical universe.

Hume has demonstrated that subjective Idealism, founded on the belief that in sense-perception we have knowledge only of impressions on the sensorium, involves universal skepticism. On the other hand Kant has demonstrated that Sense alone, without rational principles given by the mind, is equally incompetent to give real knowledge. Together they have demonstrated that both presentative intuition and rational are essential to knowledge. The mind is not passively recipient of impressions but active in knowing. The mind knows. And the postulates or principles of rational intuition belong to the very nature of knowledge. Liard, as reported by Janet, says, "As yet the Positive school has not answered the learned demonstration of Kant on the necessity of a priori principles, or rather has ignored it. It has made no addition to the old empiricism which the school of Leibnitz and Kant refuted." Any system of Positivism like that of Comte, propounded as a theory of knowledge without noticing the principles established by Hume and Kant, is not entitled to the attention of scholars. Accordingly Lange says, "The very attempt to construct a philosophical theory of things exclusively on the physical sciences must in these days be described as a philosophical one-sidedness of the worst kind."*

Geschichte des Materialismus; B. II. Sect. II. Chap. I.

I conclude, therefore, that the power of rational intuition is essential in the idea of Reason, as extension is in the idea of body. The knowledge of first principles of reason is essential to all knowledge which rises above mere impressions or phenomena, and is inherent in the nature of rational intelligence. The denial of them involves complete agnosticism. This result Fitz-James Stephen exemplifies when he says, "It is surely obvious that all physical science is only a probability, and, what is more, one which we have no means whatever of measuring. The present is a mere film melting into the past."* We accept, therefore, as the most fundamental postulate, the principle that the self-evident and necessary intuitions of the mind are true. Of this postulate H. Spencer says, "Not even a reason for doubting its validity can be given without tacitly asserting its validity."†

V. It is objected that these principles are not universally believed. It is said, If they are constitutional and self-evident, every one must believe them; and this, it is said, is not the fact.

1. In sustaining this position it is usually urged that infants and savages have no knowledge of them. As thus urged the objection is founded on misapprehension of the doctrine. It is pertinent only against innate ideas, the existence of which no one affirms, not against rational intuitions existing as constitutional norms and elements of rationality, and rising in consciousness as regulative of thought only on occasion in experience.

The customary attempt to discredit the principles and laws of thought because infants and savages are not conscious of them is unscientific. It rests on the false assumption that nothing is constitutional in man except what infants and savages are conscious of; human powers are to be ascertained not by observing what they are in mature men but only what they are in their nascent state in infancy and savagery. It is an appeal from facts to fancies, from what we know to what we do not know. This kind of reasoning would prove that it is not natural to man to have a beard, or teeth, or parental affection; or that it is not natural to an apple to bear blossoms and apples because they are not observed in the seed. We do not study the acorn to find out what the oak is, but the oak to find out what the acorn is.

The objection rests on the further mistake, in respect to savages, that a principle does not regulate thought and action until it is consciously formulated. The doctrine is that men think and act under the regula tion of these principles even when they have never consciously formulated them. The objection, therefore, is founded on a misapprehension of the doctrine. The validity of rational intuition, in its true meaning * Liberty, Equality, Fraternity, pp. 346, 347.

† Psychology, Vol. II. p. 491.

is sustained by the common consciousness of mankind; and in vindicating it we avail ourselves of this ancient argument, which Hesiod states at the end of his "Works and Days:" "The word proclaimed by the concordant voice of mankind fails not; for it is a sort of divinity."*

2. But we are told that these beliefs are not necessary even to cultivated persons. J. S. Mill says: "Any one accustomed to abstraction and analysis, who will fairly exert his faculties for the purpose, will, when his imagination has once learned to entertain the notion, find no difficulty in conceiving that in some one of the many firmaments into which sidereal astronomy now divides the universe, events may succeed one another at random without any fixed law; nor can anything in our experience or in our mental nature constitute a sufficient, or indeed any reason for believing that this is nowhere the case."† Mr. Mill held that all necessary beliefs arise from association of ideas in the life-time of an individual. He could consistently suppose that under new conditions new associations could be formed. But here he supposes new conditions which break up the old associations without forming new ones. His supposition, therefore, is directly in contradiction to his own theory. Mr. Mill does not say that he can conceive of such a world of unreason, but only that he thinks one might learn to conceive of it.

It is very common for skeptics who hold that our knowledge is unreal because known through our own reason, to tell us of a world possibly known to other minds in which right is wrong, and the angles of a triangle may be equal to six right angles, or a hollow sphere with continuous surface may be turned inside out without rupture. But when we attend to it we see that it is a mere Shemhamphorash or abracadabra, words to conjure with, which overawe the unthinking but are seen by all thoughtful persons to be sounds without meaning. Accordingly Comte and others who exclude the very ideas of cause, force, and being from scientific thought and limit it to phenomena, yet continually think and write under the regulation of the principles which they reject. The existence of the real is unavoidably asserted in every attempt to prove that knowledge is only relative; the existence of both subject and object is asserted in every proof that we know no objective reality; the knowledge what a true cause is as distinguished from an invariable antecedent is asserted in every denial of the possibility of having knowledge of a true cause; the validity of rational intuitions is appealed to in asserting that they cannot be valid;

* Φήμη δ' υποτε πάμπαν ἀπόλλυται ἦν τινα πολλοὶ

Λαοὶ φημίζουσι· Θεός νύ τις ἐστὶ καὶ ἀυτή.

† Logic, B. III. Chap. 21, § 1.

the idea of God is recognized in denying the possibility of knowing him. And whatever theory of knowledge or of agnosticism prevails, men go on, alike in common life and in scientific investigation, prosecuting work, constructing institutions, enlarging science, subduing and civilizing the earth, and all in tacit accordance with the principles regulative of all thinking.

VI. Another objection is that Reason breaks down at last in irreconcilable contradictions. Though all must necessarily believe these principles yet they are contradictory to each other. We necessarily believe each of two contradictory propositions.

1. The second idea of the reason, according to Kant, is the Cosmos. In developing the cosmological ideas, there arise certain "sophistical propositions" which are necessary "in the very nature of reason," but which are "contrary" to each other. These he calls "antinomies." His four antinomies pertain solely to his second idea of Reason, the Cosmos. In the first the thesis affirms as a necessary belief that the world is limited in time and space; the antithesis affirms as equally necessary the belief that it is not thus limited but is infinite in time and space. In the second the thesis is that the world consists of simple parts; the antithesis, that no simple substance exists. In the third the thesis is that free-will exists; the antithesis, that free-will does not exist, but every thing happens necessarily under the laws of nature. In the fourth the thesis is that an Absolute Being exists; the antithesis, that Absolute Being does not exist either in the world or out of it.

The agnosticism and materialism of this day make frequent appeals to Kant's antinomies. Prof. Clifford says that in this "famous doctrine of the antinomies "Kant first set forth the opinion, "held by great numbers of the philosophers who have lived in the brightening ages of Europe," "that at the basis of the natural order there is something which we can know to be unreasonable."* From this doctrine of the antinomies Hamilton derives his fundamental law that "thought is possible only in the conditioned interval between unconditioned contradictory extremes or poles, each of which is altogether inconceivable, but of which the one or the other is necessarily true." Accordingly he regards the causal judgment and the other first principles of reason as resulting, not from a power of positive self-evident knowledge, but from an impotence of mind to think the inconceivable and to believe the contradictory. Thus he interprets the antinomies as manifesting simply "the common principle of a limitation of our faculties. Intelligence is shown to be feeble, but not false; our nature is thus not a lie nor the

Lecture on the Aims and Instruments of Science delivered before the members of the British Association at Brighton, Aug. 19, 1872.

author of our nature a deceiver."* The truthfulness of our nature is consistent with the antinomies rightly interpreted; but it is impossible to reach this result and thus to rescue the trustworthiness of reason and the reality of knowledge, if with Hamilton we interpret the antinomies as direct contradictories.

Mansel in his "Limits of Religious Thought" accepts the doctrine that the antinomies are contradictories and uses it in defence of religious belief. He argues that if in developing religious ideas we find ourselves necessarily involved in contradictions, the fact does not invalidate our knowledge, because in philosophy and indeed in the ultimate development of thought on any subject, reason necessarily involves us in similar contradictions. It is surprising that this defence of religious belief was welcomed with exulting applause by many theologians. It is not surprising that it was also gladly welcomed by skeptics, not as proving the reality of religious knowledge, but as disproving philosophy, and ultimately the reality of all knowledge.

Through these and similar interpretations of Kant's antinomies it has come to pass that skepticism, appealing to them, habitually assumes that philosophy in the conclusions of its greatest masters has itself acknowledged its own incompetence and demonstrated that reason, on which it claims to rest, in its ultimate principles necessarily breaks down in self-contradiction.

2. If it is a fact that reason necessarily issues in the necessary belief of contradictories, the objection is fatal. Reason is no longer trustworthy, the laws which necessarily regulate all thinking are discredited, the results of thought are disintegrated, and knowledge is volatilized into empty impressions and disappears.

It is evident, also, that this objection is the only one by which it is possible to disprove the trustworthiness of the reason or the truthfulness of its necessary intuitions. Reason cannot avail itself of any faculty more rational than itself nor lift itself to any sphere of knowledge above and beyond its own, by comparison with which to disprove its own intuitions. But if its own necessary intuitions contradict each other it can know the fact, and then must also know that some of its necessary intuitions are false and that it is itself discredited as an organ of the knowledge of truth. There is no other way conceivable by which reason can know itself untrustworthy.

And it must be noticed that even here it is the authority of reason itself to which reason appeals in judging that two contradictories cannot both be true. It is the first and most fundamental principle of reason, the law of non-contradiction, the truth of which is acknowledged

*Philosophy of Common Sense, p. 20; Philosophy of the Conditioned, pp. 500, 505, Wight's Ed. of Hamilton's Philosophy.