Excerpts from The Federalist Papers, No. 15  (Alexander Hamilton):

There was a time when we were told that breaches, by the States, of the regulations of the federal authority were not to be expected; that a sense of common interest would preside over the conduct of the respective members, and would beget a full compliance with all the constitutional requisitions of the Union. This language, at the present day, would appear as wild as a great part of what we now hear from the same quarter will be thought, when we shall have received further lessons from that best oracle of wisdom, experience. It at all times betrayed an ignorance of the true springs by which human conduct is actuated, and belied the original inducements to the establishment of civil power.

Why has government been instituted at all? Because the passions of men will not conform to the dictates of reason and justice, without constraint.

Has it been found that bodies of men act with more rectitude or greater disinterestedness than individuals? The contrary of this has been inferred by all accurate observers of the conduct of mankind; and the inference is founded upon obvious reasons. Regard to reputation has a less active influence, when the infamy of a bad action is to be divided among a number than when it is to fall singly upon one. A spirit of faction, which is apt to mingle its poison in the deliberations of all bodies of men, will often hurry the persons of whom they are composed into improprieties and excesses, for which they would blush in a private capacity.

In addition to all this, there is, in the nature of sovereign power, an impatience of control, that disposes those who are invested with the exercise of it, to look with an evil eye upon all external attempts to restrain or direct its operations. From this spirit it happens, that in every political association which is formed upon the principle of uniting in a common interest a number of lesser sovereignties, there will be found a kind of eccentric tendency in the subordinate or inferior orbs, by the operation of which there will be a perpetual effort in each to fly off from the common centre.

This tendency is not difficult to be accounted for. It has its origin in the love of power. Power controlled or abridged is almost always the rival and enemy of that power by which it is controlled or abridged. This simple proposition will teach us how little reason there is to expect, that the persons intrusted with the administration of the affairs of the particular members of a confederacy will at all times be ready, with perfect good-humor, and an unbiased regard to the public weal, to execute the resolutions or decrees of the general authority. The reverse of this results from the constitution of human nature.