[Footnote 22: I might have mastered the philosophy of Kant, without waiting for the German language, in which all his capital works are written; for there is a Latin version of the whole, by Born, and a most admirable digest of the cardinal work (admirable for its fidelity and the skill by which that fidelity is attained), in the same language, by Rhiseldek, a Danish professor. But this fact, such was the slight knowledge of all things connected with Kant in England, I did not learn for some years.] Immanuel Kant was originally a dogmatist in the school of Leibnitz and Wolf; that is, according to his trisection of all philosophy into dogmatic, sceptical, and critical, he was, upon all questions, disposed to a strong _affirmative_ creed, without courting any particular examination into the grounds of this creed, or into its assailable points. From this slumber, as it is called by himself, he was suddenly aroused by the Humian doctrine of cause and effect. This celebrated essay on the nature of necessary connection--so thoroughly misapprehended at the date of its first publication to the world by its _soi-disant_ opponents, Oswald, Beattie, &c., and so imperfectly comprehended since then by various _soi-disant_ defenders--became in effect the 'occasional cause' (in the phrase of the logicians) of the entire subsequent philosophic scheme of Kant--every section of which arose upon the accidental opening made to analogical trains of thought, by this memorable effort of scepticism, applied by Hume to one capital phenomenon among the necessities of the human understanding. What is the nature of Hume's scepticism as applied to this phenomenon? What is the main thesis of his celebrated essay on cause and effect? For few, indeed, are they who really know anything about it. If a man really understands it, a very few words will avail to explain the _nodus_. Let us try. It is a necessity of the _human_ understanding (very probably not a necessity of a higher order of intelligences) to connect its experiences by means of the idea of _cause_ and its correlate, _effect_: and when Beattie, Oswald, Reid, &c. were exhausting themselves in proofs of the indispensableness of this idea, they were fighting with shadows; for no man had ever questioned the practical necessity for such an idea to the coherency of human thinking. Not the practical necessity, but the internal consistency of this notion, and the original right to such a notion, was the point of inquisition. For, attend, courteous reader, and three separate propositions will set before your eyes the difficulty. _First Prop._, which, for the sake of greater precision, permit me to throw into Latin:--_Non datur aliquid_ [A] _quo posito ponitur aliud_ [B] _a priori_; that is, in other words, You cannot lay your hands upon that one object or phenomenon [A] in the whole circle of natural existences, which, being assumed, will entitle you to assume _a priori_, any other object whatsoever [B] as succeeding it.