The continuance of emulation among states must depend on the degree of equality by which their forces are balanced; or on the incentives by which either party, or all, are urged to continue their struggles. Long intermissions of war, suffer, equally in every period of civil society, the military spirit to languish. (The reduction of Athens by Lysander, struck a fatal blow at the institutions of Lycurgus; and the quiet possession of Italy, happily perhaps for mankind, had almost put an end to the military progress of the Romans. After some years repose, Hannibal found Italy unprepared for his onset, and the Romans in a disposition likely to drop, on the banks of the Po, that martial ambition, which being roused by the sense of a new danger, afterwards, carried them to the Euphrates and the Rhine.) States, even distinguished for military prowess, sometimes lay down their arms from lassitude, and are weary of fruitless contentions; but if they maintain the station of independent communities, they will have frequent occasions to recall, and to exert their vigour. Even under popular governments, men sometimes drop the consideration of their political rights, and appear at times remiss or supine; but if they have reserved the power to defend themselves, the intermission of its exercise cannot be of long duration. Political rights, when neglected, are always invaded; and alarms from this quarter must frequently come to renew the attention of parties. The love of learning, and of arts, may change its pursuits, or droop for a season; but while men are possessed of freedom, and while the exercises of ingenuity are not superseded, the public may proceed, at different times, with unequal fervour; but its progress is seldom altogether discontinued, or the advantages gained in one age are seldom entirely lost to the following. If we would find the causes of final corruption, we must examine those revolutions of state that remove, or withhold, the objects of every ingenious study or liberal pursuit; that deprive the citizen of occasions to act as the member of a public; that crush his spirit; that debase his sentiments, and disqualify his mind for affairs. SECTION III. OF RELAXATIONS IN THE NATIONAL SPIRIT INCIDENT TO POLISHED NATIONS. Improving nations, in the course of their advancement, have to struggle with foreign enemies, to whom they bear an extreme animosity, and with whom, in many conflicts, they contend for their existence as a people. In certain periods, too, they feel in their domestic policy inconveniencies and grievances, which beget an eager impatience; and they apprehend reformations and new establishments, from which they have sanguine hopes of national happiness. In early ages, every art is imperfect, and susceptible of many improvements. The first principles of every science are yet secrets to be discovered, and to be successively published with applause and triumph.