In order to have a general and comprehensive knowledge of the whole, we must be determined on this, as on every other subject, to overlook many particulars and singularities, distinguishing different governments; to fix our attention on certain points, in which many agree; and thereby establish a few general heads, under which the subject may be distinctly considered. When we have marked the characteristics which form the general points of coincidence; when we have pursued them to their consequences in the several modes of legislation, execution, and judicature, in the establishments which relate to police, commerce, religion, or domestic life; we have made an acquisition of knowledge, which, though it does not supersede the necessity of experience, may serve to direct our inquiries, and, in the midst of affairs, give an order and a method for the arrangement of particulars that occur to our observation.
When I recollect what the President Montesquieu has written, I am at a loss to tell, why I should treat of human affairs; but I too am instigated by my reflections, and my sentiments; and I may utter them more to the comprehension of ordinary capacities, because I am more on the level of ordinary men. If it be necessary to pave the way for what follows on the general history of nations, by giving some account of the heads under which various forms of government may be conveniently ranged, the reader should perhaps be referred to what has been already delivered on the subject by this profound politician and amiable moralist. In his writings will be found, not only the original of what I am now, for the sake of order, to copy from him, but likewise probably the source of many observations, which, in different places, I may, under the belief of invention, have repeated, without quoting their author.
The ancient philosophers treated of government commonly under three heads; the Democratic, the Aristocratic, and the Despotic. Their attention was chiefly occupied with the varieties of republican government, and they paid little regard to a very important distinction, which Mr. Montesquieu has made, between despotism and monarchy. He too has considered government as reducible to three general forms; and, "to understand the nature of each," he observes, "it is sufficient to recal ideas which are familiar with men of the least reflection, who admit three definitions, or rather three facts: that a republic is a state in which the people in a collective body, or a part of the people, possess the sovereign power; that monarchy is that in which one man governs, according to fixed and determinate laws; and a despotism is that in which one man, without law, or rule of administration, by the mere impulse of will or caprice, decides, and carries every thing before him."