Whatever we know must be in the number of the primitive      data, or of the conclusions which can be drawn therefrom.—
     J.S. Mill
To have reached, in the study of observed phenomena, the point of perception indicated in this motto, and to feel the full force of the remark, is to have imbibed the spirit of science—-whose traits are dear distinctions, accurate classification, and strict reference to primitive data. The bases of all science are methodical facts. The first step to the perfection and enlargement of a science is the resolution of its propositions into axioms, and into propositions which are to be proved. Dr. Reid observes—'This has been done in mathematics from the beginning, and has tended greatly to the emolument of that science. It has lately been done in natural philosophy, and by this means that science has advanced more in 160 years than it had done before in 2,000. Every science is in an unformed state until its first principles are ascertained; after this it advances regularly, and secures the ground it has gained.'
Classification is one of the first steps to Science. The maxim in government, divide and conquer, retains, when applied to science, all its wisdom without its machiavelialism. The young grammarian reduces the mass of words, that so threaten to confound his powers, to a few natural classes, and he conquers them separately with ease.
'The single power by which we discover resemblance or relation in general, is a sufficient aid to us in the perplexity and confusion of our first attempts at arrangement. It begins by converting thousands, and more than thousands, into one; and, reducing in the same manner the numbers tiros formed, it arrives at last at the few distinctive characters of those great comprehensive tribes, on which it ceases to operate, 'because there is nothing left to oppress the memory or the understanding.'*
     * Brown's Moral Philosophy, Lect, xvi.
Merell has spoken more comprehensively on this subject—'That human knowledge dees not consist in the bare collection and enumeration of facts; this alone would be of little service were we net to attempt the classification of them, and to educe from such classification general laws and principles. The knowledge, which consists in individual truths, could never be either extensive ear definite—for the multiplicity of objects which then must crowd in upon the mind only tends to confound and perplex it, while the memory, overburdened with particulars, is not able to retain a hundredth part of the materials which are collected. To prevent this, the power el generalisation comes to our aid, by which the individual facts are so classified under their proper conceptions, that they may at the same time be more easily retained, and their several relations to all other branches of knowledge accurately defined. The colligation and classification of facts, then, we may regard as the two first steps, which are to be taken in the attainment of truth.'*
Aristotle, says Morell, classified the matter, Kant the forms. Aristotle was the first man who undertook the gigantic task of reducing the multiplicity of all the objects of human knowledge to a few general heads—-1. Substance. 2. Quality. 3. Quantity. 4. Relation. Action. 6. Passion. 7. Place. 8. Time. 9. Posture. 10. Habit. Aristotle's philosophy was objective, Kant's subjective. Kant's categories were twelve. 1. Unity. 2. Plurality. 3. Totality. 4. Affirmation. Negation. 6. limitation. 7. Substance. 8. Casualty. 9. Reciprocity. 10. Possibility. 11. Actuality. 12. Necessity.
'It is a fundamental principle in logic, that the power of framing classes is unlimited as long as there is any (even the smallest) difference to found a distinction upon.**
What Geoffroy Saint Hilaire has said of natural history is applicable to all science:—'The first problem to be solved by him who wishes to penetrate deeply into this; study, consists evidently in the formation of clear and precise distinctions between the various brings. This is the most elementary problem, in so-far as it precedes all the others; but it is in reality, in most cases, complicated and full of difficulties. Its accurate solution requires—first, Observation, which makes known the facts; next, Description, which fixes them permanently; then Characterisation, which selects and displays prominently the most important of them—and lastly, Classification, which arranges them in systematic order.'***
Of the value of classification, Lamartine has given a fine illustration:——'Montesquieu had sounded the institutions and analysed the laws of all people. By classing governments he had compared them, by comparing them he passed judgment on them; and this judgment brought out, in its bold relief and contrast, on every page, right and force, privilege and equality, tyranny and liberty.'****
     * Morell's Hist. of Speculative Phil., p. 34, vol. 1.
 
     ** Mill, p. 165, vol. 1.
 
     *** T. W. Thornton: Reasoner No. 72, p. 664.
 
     **** Lamartine's Hist. Girondists, pp. 14-15, vol. 1.
Familiarity with the characteristics of science imparts considerable power for the detection of fallacy. A logician is imperfect without scientific tastes and habits. The man of science has all his knowledge systematised and arranged. What other people have in confusion, he has in order. The elements of knowledge are, more or less, as has been observed, known to all men—but in their perfect, communicable, and usable state, they are-known only to the educated and scientific man. What training is to the soldier, science is to the thinker. It enables him to control all his resources and employ his natural powers to the best advantage. It is this which constitutes the superiority of the educat............