But what from the analogy of water waves has been inferred to be true of light waves must logically be concluded about the still more rapid waves supposed by Professor Crookes to account for the distant influence of one person on another. When, therefore, he talks of rays piercing the densest medium and passing along the straight path, and of brain waves going straight to the goal, he is using mere abstractions which cannot fail to mislead ordinary men into thinking falsely that there is such a thing as a brain wave really emitted and moving like a projectile from person to person. It is most important to undeceive oneself. All that could really happen is that the influencing person should by thought somehow make some portion of matter adjacent to himself vibrate, and thus make the next portion vibrate, and so on, without these successive portions moving onwards, until at last the portion of matter adjacent to the influenced person should by vibrating somehow produce in him the thought required. What, then, becomes of the brain waves?

Now, it makes all the difference in the world to the plausibility of the professor's hypothesis how it is expressed. Expressed as he expresses it in the misleading language of abstraction, it looks as if nothing could be simpler than a brain wave passing from one person to another. Expressed in accordance with the concrete reality of things, this apparently simple hypothesis bristles with difficulties. How does the thought of the influencing person, which in our experience only acts by slow nervous and muscular motion, make particles vibrate with a velocity many times more rapid than that of light? What are these vibrating particles, and what their vibration? Surely not brain particles nor brain waves? If, again, between the influencing and the influenced person there is nothing but a succession

of physical particles physically vibrating one after another, and no real onward motion of a so-called brain wave, how do the physical vibrating particles immediately adjacent to the influenced person produce in him a thought which in our experience requires different stimuli acting on the nerves of the five senses?

The bare proposition of these questions shows that Professor Crookes has gone far beyond the logical rules of scientific hypothesis by which the undulating action of water has been successfully extended to sound and light. In sound, the source -e.g. the string of a violin, moves and makes successive particles of air move successively till at last they make the auditory nerves move; here there is no hypothesis either of the agent, air, or of the laws of its motion. In light, the sun moving with heat makes successive portions of ether move successively till at last they make the optic nerves move; here there is hypothesis of the agent, ether, but not of the laws of its motion. On the other hand, in the supposed telepathic influence from person to person almost everything is supposed. The fact that the thought of one person produces the thought of another without the agency of the recognized organs of sense is not yet proved; to explain this supposed fact, thought in the influencing person is supposed to produce, without the ordinary moving organs, a supposed enormous velocity with which supposed particles make one another move, and finally these are supposed to produce, without the ordinary action of the sensory organs, thought in the influenced person. Here is hypothesis of the fact, hypothesis of the agent, and hypothesis of the laws by which thought is the cause of vibrations in that agent at one end, and the effect of vibrations in that agent at the other end, of the hypothetical telepathic chain. But, according to the rules of logic, we ought not

to hypothesize facts at all; we may hypothesize the agent alone, or the laws alone; but we must not hypothesize an unknown agent obeying unknown laws of action.

THE CONSOLATIONS OF TRUTH

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Dr. James Gairdner (1828-1912) was an historian and official in the Public Record Office. Although', as he wrote, not generally a reader of philosophic writings', he contributed a letter to Literature' called The Consolations of Truth', on Feb. 18, 1899. His second letter, in answer to what he called Case's careful reply', appeared on February 25.

FROM Literature, FEBRUARY 23, 1899.

Dr. Gairdner, in order to explain the consolation of truth, advances a theory in last week's Literature that we know truth from falsehood by a sense of harmony which gives the mind satisfaction. But there is consolation in falsehood and fiction as well as in truth and fact. There are assertions which are satisfactory though false, and there are truths which bring the reverse of satisfaction to the mind. Why does a doctor falsely give hope where there is no hope? Simply to satisfy his patient or his patient's relatives. What satisfaction is there in knowing the worst when you are told the truth that you have cancer in the stomach, and expect to die a disgusting death? None, absolutely none. Nor does the substitution of truth for doubt take away half the sting of an evil, as Dr. Gairdner supposes; on the contrary, a man often bears with an evil because he only half believes in it. We cannot know truth by a sense of satisfaction when satisfaction is absent. How, then, do we know it?

Man has two ways of knowing reality, sense and reasoning from sense; and, in consequence, has the power of arriving at true judgements. Sensory judgements are true when they agree with any

reality which is directly perceived by sense; for example, it is true, though unsatisfactory, to judge that I am ill when I really feel ill, and false to judge that I am well, however consoling. Rational judgements are true when they agree with any reality which is logically inferred by reason in many degrees of indirectness from sense, whether with mathematical or with moral certainty. For example, it is true and satisfactory to judge that the Cunard Company has, after all, never lost a ship, and it is equally true to judge that the Mohegan was wrecked on the Manacles by steering a wrong course, although here there is nothing but humiliation to be got out of this truth. In short, known truth is the agreement of our judgements with the realities which we perceive by sense and infer by reason, whether this harmony gives the mind satisfaction or not.

Truth is usually, but not universally, satisfactory. Hence we desire to know it more often than not; and we always desire to know it when we expect that it will satisfy us, either as a means or as an end. We value it for its utility because knowledge gives power, and we value it for its own sake because, as Aristotle says, all men desire knowledge by nature. Man lives by the truth and loves the truth itself. He usually pursues it as usually satisfactory. But we must be careful not to exaggerate this pursuit of it. On the one hand, man's desire of the truth is not identical nor even coincident with his knowledge. Truth is often forced upon him quite involuntarily, and it makes no difference to his knowledge of it whether an involuntary truth is or is not palatable; whether, for example, one hears of an unexpected legacy, or finds that one owes one's tailor £50 instead of £20. There are then involuntary and painful truths which we discover without desire, and know without satisfaction. On the other hand, the desire of the truth is itself limited.

H h

Even when we pursue the truth as satisfactory, we sometimes know it without satisfaction. Although we usually desire to know it as usually satisfactory, it sometimes turns out contrary to expectation, as when Bluebeard's wife unlocked the cupboard and found the skeletons of her predecessors. Moreover, we do not always desire to know it at all. One frequently says, 'Don't tell me,' or, 'I don't want to know,' when one expects that the knowledge of the truth will give no satisfaction to the mind. 'Where ignorance is bliss, 'tis folly to be wise.' Man stands at a disadvantage in the face of the greatness of nature. It is not for him to choose facts, nor when he will discover them, nor whether they will satisfy him. He is lucky enough if, on the whole, he is satisfied. By sense and reason he is able to know the truth, whether he is satisfied or not, and often he knows it involuntarily, painfully, without any desire to know it beforehand, or any satisfaction to be found in it afterwards, nay, sometimes against his expectation and desire, and when he would much rather have remained in blissful ignorance. He has to assent, to acquiesce, to stop thinking when convinced of the truth of a conclusion; but conviction is not consolation, and to come to a conclusion is not necessarily to become happy. The knowledge of the truth is an intellectual consequence of sense and reason, independent of the practical satisfaction of the mind. Feb. 20, 1899.

FROM Literature, MARCH 11, 1899.

Dr. Gairdner, if I understand him rightly, holds that there is always satisfaction in knowing the truth, even where the truth is painful; and that we know truth from falsehood only by this satisfaction. I, on the other hand, deny the first proposition, and contend that we know truth from falsehood only by sense and reasoning.