are different kinds of ignorance. In the first place there is honest ignorance arising from the natural weakness of our faculties and the remoteness of scientific data. In the second place, there is dishonest ignorance (dishonesty arising from different motives), which pretends to know what it does not know; to see what it does not see. Sometimes we have a medical man, say, boldly and unblushingly prescribing for a patient although ignorant of his malady. This is the quack, the dishonest, ignorant person. On the other hand, we have the upright medical man who is prepared to say whenever necessary—“ This case baffles me; I must consult with some other fellow about it." Nothing shameful here. It is a confession of honest ignorance, So, in all other matters. Honest ignorance recognising its ignorance, need not be ashamed. We are all terribly ignorant. Our best knowledge only touches, as it were, the fringes of the Universe. It is only dishonest ignorance (ignorance which pretends to know) or ignorant ignorance (which knows not that it is ignorant), that is shameful and hateful.

Montaigne on ignorance.-There is a notable passage in Montaigne on this subject. "Whoever will be cured of ignorance must confess it. Iris is the daughter of Thaumantis. Admiration (ie. wonder) is the foundation of all philosophy, Inquiry the progress, and Ignorance the end. Nay in truth there is a sort of Ignorance, strong and generous, that yields nothing in honour and courage to knowledge; an Ignorance of which to conceive, requires no less knowledge than to conceive of knowledge itself. . . . Let us take up some form of arrest which says-the Court understands nothing of the matter, more freely and ingenuously than the Areopagites did, who finding themselves perplexed with a cause they could not unravel, ordered the parties to appear again after a hundred years." 1 The attaining of this knowledge of our ignorance 1 Essays, vol. iii. pp. 324-5.

is indeed a necessary step in the acquisition of knowledge, and can scarcely be too much insisted on.

5. The Unknowable in Life and Death.-What, again, does anybody know of the real nature of Life and Deaththese immense facts of daily experience? Almost nothing but the dread facts themselves. The "why" of them is almost wholly hidden from our view. It may not be so for ever. The time is approaching, perhaps, when we may become acquainted more fully with the proximate causes of vital efficiency, as we are at present acquainted with some of the proximate causes of mechanical efficiency; but that time is not yet. At present we do not even know proximately why our blood is warm (cur res sit?). We are only acquainted with the fact (rem esse). What do we know of the real nature of organic growth, or organic decay? Organic accumulation of matter? Cellular growth? How comes it about? Very wonderful all, but quite inscrutable. Decay chemical metamorphosis and dispersal of matter and bacterial ravages, we are also acquainted with; but as to the real cur res sit of such processes? The prudent man can say nothing about it he can only wonder. Then after disease has proceeded

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a certain length. . . ?

What is the use, for example, of a lucubration like the following?" To him who has learned to consider bodies as what they truly are, a multitude of separate and independent corpuscles, there is no change of identity, and cannot be any change of identity, in all the phenomena or changes of the Universe. The atoms which alone existed continue as before; and all which constitutes the phenomena, or variations of successive phenomena, is a change of their place or tendency." 1 What is this but ignorance deceiv

1

1 Brown: Philosophy of the Human Mind, vol. i. p. 293. Comte writes that the so-called explanations of colour-the "supposed faculty of reflecting or transmitting such and such a kind of rays, or of exciting such and such an order of ethereal vibrations, in virtue of certain supposed arrangements

ing itself with words-words with a kind of learned clang about them? What does anybody know of the alleged "multitude of independent and separate corpuscles"? Nothing, of course. Who is to give us any warranty of their existence, even? Nobody. Therefore the more of that kind of scientising, the worse; the less, the better. If Knowledge and Wisdom alone, wrote books!

It is by no means easy to get at truth always; but it is surely remarkably easy to be quite silent about what you don't know; or to be contented to ask modest questions about it. The general observation, in practice, of this one rule of philosophic caution, would subvert Babel.

6. The Unknowable in Mental Processes.—Briefly view the same fact, the limitation of our knowledge, in connection with mental processes. "Every effect is only produced by the concurrence of at least two causes (and by cause, be it observed, I mean everything without which the effect could not be realised), and as these concurring and co-efficient causes, in fact, constitute the effect, it follows that the lower we descend in the series of causes, the more complex will be the product; and that the higher we ascend it will be more simple."1 Let us try to ascend a bit. For example, visual perception is the result of various known causes and conditions: (1) We require a being possessed of visual organs; (2) he must use these organs; (3) to see, he requires the aid of light, and (4) the existence of an external visual object in a certain position relative to the organs. So far we can go. In the circumstances indicated, we can see. This is the fact. Cur res sit? For centuries and centuries, philosophers have tried to answer the question, and have invented

of the molecules, are more difficult to conceive than the fact itself, and are in truth as absurd as the explanations that Molière puts into the mouth of his metaphysical doctors." Positive Philosophy, vol. i. p. 271 (Martineau's tr.).

1 Hamilton: Lectures, vol. i. p. 59. He is, of course, speaking of proximate or secondary causes.

The

cartloads of theories to account for this fact of vision, but absolutely in vain. They know as little about it to-day, as when they began the speculation. All that they or we know about it down to this date, is the fact that, in the circumstances stated, we do actually see. Even Hume allows this:-" As to those impressions which arise from the senses, their ultimate cause is, in my opinion, perfectly inexplicable by human reason; and it will always be impossible to decide with certainty whether they arise immediately from the object, or are produced by the creative power of the mind, or are derived from the Author of our being." 1 All we know about it, as I have said, is that we do actually see. Now, how is this? right answer, I think, is that the inquiry touches a subject beyond our reach. To this day we know practically nothing of the nature of the ego,-the self within us, the seeing subject. Our powers of selfobservation do not sink so deep. Beyond noting the amazing organisation of the material eye, and tracing the laws of visual perception as revealed to us in experience, we can discover no sufficient data, no facts, upon which to make induction and conclusion as to the veritable why" of seeing; and until some such further data can be discovered, we are absolutely unable to carry our science of perception any higher. We are simply brought to a standstill when we arrive at the facts given us in our inner consciousness. It is to be noticed, however, that although in our present state of being, we are

1 Treatise of Human Nature (Reference lost).-Amongst later writers, Mr. Herbert Spencer's huge volumes throw no additional light whatever on the problem of perception. Mr. Mivart happily says-"The intellect apprehends through sense what is beyond sense.' Nature and Thought, p. 205. M'Cosh notes-"Reid and Stewart are ever telling us that they have obtained only partial glimpses of truth. All the great masters of the (Scottish) School not only admit but are at pains to show that there are mysteries in the mind of man and in every department of human speculation, which they cannot clear up." Scottish Philosophy, pp. 10-11.

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absolutely frustrated in our attempts to obtain any articulate knowledge of the "why" of visual perception, it is not inconceivable that we might have been endowed with higher powers through which we might have obtained such knowledge, or carried it upwards at all events; and it is quite conceivable that in a future state of existence— of which I joyfully think there are strong indications, we may be furnished with this higher knowledge, or indeed with those higher powers. "Now we see as through a glass, darkly"; now we do but know in part. Later, the Apostle thinks, we shall have a clearer view of things— which seems to be a very reasonable anticipation.

So with sonal perception; or sapid perception; or odorous or tactile perception. In no case can we get much beyond the facts of consciousness; in no case can we give any adequate explanation of these facts. All offered explanations seem to be so many vexing but ludicrous proofs of human ignorance or presumption. The men who attempt to furnish us with such explanations, beyond tracing the laws of our sensations and perceptions, appear to be as fatuously engaged as the drunkard who attempted to pull the moon out of the ditch. It would be of infinite advantage to Science if all the Schools would religiously observe these truths.

Dr. Hook's theory of ideas.-Take Dr. Robert Hook's theory of ideas. He assumes them to be "material substance; and thinks that the brain is furnished with a proper kind of matter for fabricating the ideas of each sense. The ideas of sight, he thinks, are formed of a kind of matter resembling the Bononian Stone, or some kind of phosphorus; that the ideas of sound are formed of some matter resembling the chords or glasses which take a sound from the vibrations of the air; and so of the rest.

"The soul, he thinks, may fabricate some hundreds of those (so-called) ideas in a day; and that as they are