CHAPTER II.

GNOSIOLOGY.

SECT. I.-ON KNOWLEDGE.

WHAT is Science (E16τnun)? is the question put by Socrates in Plato's subtle dialogue of Theatetus. But the word "science" has two meanings. In one sense it can be defined. It is knowledge, arranged, correlated, or systematized. In this sense we speak of astronomy, geology, logic and other sciences. But the word had, at least in Greek, another signification, and meant simply knowledge; and we may suppose the question to be put, What is Knowledge? To this the reply must be, that we cannot positively define knowledge, so as to make it intelligible to one who did not know it otherwise. Still we can, by analysis, separate it from other things with which it is associated,-such as sensations, emotions, and fancies,-and make it stand out distinctly to the view of those who are already conscious of it. The science which thus unfolds the nature of knowledge may be called Gnosiology, or Gnosilogy (from yvoóis and Aóyos). I prefer this to Epistemology which would signify the science of arranged knowledge.

This science should be prosecuted in the same method as every other which has to do with facts, that is, in the Inductive. Its main office is to inquire into the nature of the knowing powers, to determine the mode of the operation of each, and the amount, and, what is equally important, the kind of knowledge which each is fitted to impart. This is what I have been doing all throughout this treatise. I am not to recapitulate the processes here. Yet it will be necessary to show, in a few sentences, how the method

followed and the results reached have a bearing on Gnosiology. Commencing with sense-perception, I drew the distinction between our original and acquired perceptions, and endeavoured to ascertain what are our primary perceptions through the various senses, and also painted out the difference between sensation and perception. Proceeding to self-consciousness, I sought to estimate the primary knowledge which we have of self as acting or exercising some property. Coming to the reproductive powers, I showed that here the faith element appears, and I pointed out the relation in which faith and cognition stand to each other, and unfolded the convictions which we have in regard to space, time, and the infinite. Looking to the objects thus made known or believed in, the mind pronounces a set of judgments, and I drew out a classification of these, and sought to unfold their nature. But the mind has not only the capacity of discovering the true, it has a power of discovering the good; and I was at pains to show wherein our moral convictions are analogous to our intellectual convictions, and wherein they differ from them.

From this statement it appears that the metaphysician, in prosecuting his pursuits, should be able to distinguish-(1.) between our cognitions and certain associated states; (2.) between one kind of conviction and another; and (3.) between our original and acquired convictions. Almost all errors, excesses, and defects in philosophy have proceeded from overlooking or mistaking these all-essential differences. Thus some confound their sensations, or their feelings, or their inferences, or even their fancies, with their primary knowledge. Some imagine that our primitive convictions must all be alike in every respect, and that what is affirmed legitimately of one may be affirmed of any other, or of all; that, for example, our intellectual and moral cognitions all disclose the same sort of reality as is to be found in the perceptions of sense. Again, it is by failing to distinguish between the convictions guaranteed by our constitution and those reached by experience, that

1 In memory-(1.) the event is retained; (2.) comes up according to the laws of association; (3.) comes with a phantasm; (4.) is recognized as having been before the mind in time past. The fourth, or recognitive power, involving faith, and with the idea of time in the concrete, is the essential element in memory, but is often overlooked by later psychologists, German and British.

persons have been led to suppose that their senses or faculties deceive them.

In Plato's dialogue, Socrates is represented as exposing all the answers given by Theatetus, but without explicitly furnishing one of his own. He shows, first, that science is not sense-perception (aï60n615). It is true that all knowledge is not derived from this source; but a certain portion is, though in order to estimate it exactly, we must be careful to separate from it associated sensations, and stand up for the positive veracity only of constitutional convictions. He shows, secondly, that science is not opinion or judgment (sósa dλnons). Yet, by judgment on materials supplied, we can and do reach truth, and have criteria-as will be shown in next paragraph-by which to test it. He then shows that science cannot consist in judgment with a rational process (uɛra Aoyov) accompanying it. It is admitted that no rational process can add to the force of truth, but analysis and explication can settle for us wherein lies the force of truth.

But the question is here started, Can there be a criterion of truth? The inquiry has commonly been made by those who seek for an absolute law, or for one short and easy rule, which may at once determine for us as to every given or supposable asseveration, whether it is or is not true. Now it may be confidently asserted that such a criterion is not discoverable by man, nor can he so much as know whether it is possible in the nature of things, or available to any other intelligences. But I have laboured to show that there are tests of primitive truth not very difficult of application; these tests are self-evidence and necessity, and, as auxiliary to these, catholicity. Again, of that portion of fundamental truth which may be ranked under the head of Analytic Judgments a priori, there are very stringent tests in the Laws of Identity, NonContradiction, and excluded Middle. Very definite rules for testing Synthetic Judgments a priori may be found in the maxims which have been enunciated in treating of the various classes of Primitive Judgments. As to experiential truth, there are in many departments tests quite sufficient both for scientific and practical purposes, but these are so many that they cannot be numbered here; they will be found in a looser or more rigid form in treatises

which discuss the various branches of knowledge, and they are now being combined in works of inductive or applied logic. Each advanced science and art has its own rules of evidence, competent to determine for it what is truth in its own department and within fields open to man's observation. But there can be no rule found by the physicist, or devised by the metaphysicist, to determine all questions, or questions beyond the range of man's observation,as, for example, whether the Dog-star is or is not inhabited, or whether there are other substances in the universe besides mind and matter.

SECT. II.-ON THE ORIGIN OF OUR KNOWLEDGE AND IDEAS.

We must now enter upon the inquiries in which Locke, and five or six friends who met in his chamber in Oxford, found themselves involved, and which issued twenty years afterwards in the famous Essay on the Human Understanding. Starting with a far different topic, they found themselves quickly at a stand, and it came into the thoughts of Locke that before entering "upon inquiries of that nature, it was necessary to examine our own abilities, and see what objects our understandings were or were not fitted to deal with." It follows from the account given in the preceding pages that man's knowledge is derived from Four Sources :

FIRST, We obtain knowledge from sensation, or rather senseperception. Such is the knowledge we have of body, and of body extended and resisting pressure, and of our organism as affecting us, or as being affected with smells, tastes, sounds, and colours.

SECONDLY, We obtain knowledge from self-consciousness. Such is the knowledge we have of self, and of its modes, actions, and affections, say, as thinking, feeling, resolving.

I am convinced that from these two sources we obtain not all our knowledge, but all the knowledge we have of separately existing objects. We do not know, and we cannot, as will be shown forthwith, so much as conceive of a distinctly existing thing, excepting in so far as we have become acquainted with it by means of sensation and reflection, or of materials thus derived. Here Locke

held by a great truth, though he did not see how to limit it on the one hand, nor what truths required to be added to it on the other. For man has other sources of knowledge.

THIRDLY, By a further Cognitive or Faith exercise we discover Qualities and Relations in objects which have become known by the senses external and internal. Of this description are the ideas which the mind forms of such objects as space, time, the infinite, the relation between cause and effect, and moral good. There is a wide difference between this Third Class and the Second, though the two have often been confounded. In self-consciousness we look simply at what is passing within, and as it passes within. But the mind has a capacity of discovering further qualities and relations among the objects which have been revealed to it by sensation and consciousness. What these are, must be determined by such an inquiry, as we have undertaken in this treatise, into the number and nature of our Primitive Beliefs and Judgments. This third kind of knowledge seems to be what is referred to by those who represent the mind or intellect itself as a source of ideas.1 But this account can be admitted only on its being understood that the mind notices these qualities and relations as in objects which have been made known by sensation and reflection.

FOURTHLY, The mind can reach truth necessary and universal, that is, universally true. This may be regarded as knowledge, and it is knowledge which goes far beyond that derived from the other sources. We are sure that these two straight lines which go parallel for the smallest possible space, may be extended infinitely, without being ever nearer each other. We are certain that gratitude and holy love, which are good here, must be good all through the wide universe. But this fourth kind of cognition is not independent of the other three kinds. All the necessary truth we can

1 As by Leibnitz, when to the principle "nihil est in intellectu quod non prius fuerit in sensu," he adds, "nisi intellectus ipse." The expression is vague. Professor Webb remarks upon it, Intellectualism of Locke, p. 85: "If Phyllis were to say to Amaryllis, there is nothing in the cheese-vat which was not previously in the milk-pail,' and Amaryllis were to add, 'except the cheese-vat itself,' the addition would be regarded as palpably unmeaning."