When principles thus casually applied in one part to matters intended to be afterwards treated of in another, came to be taken up a-new, they involved me in what may appear prolixity. This I found most unavoidable, when I was led to thoughts which were new to myself, and consequently such as must cost me the greatest labour to set in a clear and distinct point of view. Had I been master of my subject on setting out, the arrangement of the whole would have been rendered more concise: but had this been the case, I should never have been able to go through the painful deduction which forms the whole chain of my reasoning, and upon which, to many readers, slow in forming combinations, the conviction it carries along with it in a great measure depends: to the few, again, of a more penetrating genius, to whom the slightest hint is sufficient to lay open every consequence before it be drawn, in allusion to Horace, I offer this apology, _Clarus esse laboro, prolixus fio_. The path I have taken was new to me, after all I had read on the subject. I examined what I had gathered from others by my own principles; and according as I found it tally with collateral circumstances, I concluded in its favour. When, on the other hand, I found a disagreement, I was apprized immediately of some mistake: and this I found constantly owing to the narrowness of the combinations upon which it had been founded. The great danger of running into error upon particular points relating to this subject, proceeds from our viewing them in a light too confined, and to our not attending to the influence of concomitant circumstances, which render general rules of little use. Men of parts and knowledge seldom fail to reason consequentially on every subject; but when their inquiries are connected with the complicated interests of society, the vivacity of an author’s genius is apt to prevent him from attending to the variety of circumstances which render every consequence, almost, which he can draw, uncertain. To this I ascribe the habit of running into what the French call _Systemes_. These are no more than a chain of contingent consequences, drawn from a few fundamental maxims, adopted, perhaps, rashly. Such systems are mere conceits; they mislead the understanding, and efface the path to truth. An induction is formed, from whence a conclusion, called a principle, is drawn; but this is no sooner done, than the author extends its influence far beyond the limits of the ideas present to his understanding, when he made his deduction.