And Knox from his full park to battle brings
His brazen tubes, the last resort of kings.

Book V. Line 665.

Ultima ratio regum; a device of Louis XIV engraved on his ordnance, and afterwards adopted by other powers. When we consider men as reasonable beings and endowed with the qualities requisite for living together in society, this device looks like a satire upon the species; but in reality it only proves the imperfect state to which their own principles of society have yet advanced them in the long and perhaps interminable progress of which they are susceptible. This ultima ratio being already taken out of the hands of individuals and confided only to the chiefs of nations is as clear a proof of a great progress already made, as its remaining in the hands of those chiefs is a proof that we still remain far short of that degree of wisdom and experience which will enable all the nations to live at peace one with another.

There certainly was a time when the same device might have been written on the hatchet or club or fist of every man; and the best weapon of destruction that he could wield against his neighbour might have been called ultima ratio virarum, meaning that human reason could go no farther. But the wisdom we have drawn from experience has taught us to restrain the use of mortal weapons, making it unlawful and showing it to be unreasonable to use them in private disputes. The principles of social intercourse and the advantages of peace are so far understood as to enable men to form great societies, and to submit their personal misunderstandings to common judges; thus removing the ultima ratio from their own private hands to the hands of their government.

Hitherto there has usually been a government to every nation; but the nations are increasing in size and diminishing in number; so that the hands which now hold the ultima ratio by delegation are few, compared with what they have been. I mean this observation to apply only to those extensions of nationality which have been formed on the true principles of society and acquiesced in from a sense of their utility. I mean not to apply it to those unnatural and unwieldy stretches of power, whose overthrow is often and erroneously cited as an argument against the progress of civilization; such as the conquests of Alexander, the Roman generals, Omar, Gengis Khan and others of that brilliant description. These are but meteors of compulsive force, which pass away and discourage, rather than promote, the spirit of national extension of which I speak.

This spirit operates constantly and kindly; nor is its progress so slow but that it is easily perceived. Even within the short memorials of modern history we find a heptarchy in England. Ossian informs us that in his time there was a great number of warlike states in Ireland and as many more in Scotland. Without going back to the writings of Julius Cesar to discover the comparative condition of France, we may almost remember when she counted within her limits six or seven different governments, generally at war among themselves and inviting foreign enemies to come and help them destroy each other. Every province in Spain is still called a kingdom; and it is not long since they were really so in fact, with the ultima ratio in the hands of every king.

The publicist who in any of those modern heroic ages could have imagined that all the hundred nations who inhabited the western borders of Europe, from the Orknies to Gibraltar, might one day become so far united in manners and interests as to form but three great nations, would certainly have passed for a madman. Had he been a minister of Phararnond or of Fingal he could no more have kept his place than Turgot could keep his after pointing out the means of promoting industry and preventing wars. He would have been told that the inhabitants of each side of the Humber were natural enemies one to the other; that if their chiefs were even disposed to live in peace they could not do it; their subjects would demand war and could not live without it. The same would have been said of the Seine, the Loire and every other dividing line between their petty communities. It would have been insisted on that such rivers were the natural boundaries of states and never could be otherwise.

But now since the people of those districts find themselves no longer on the frontiers of little warlike states, but in the centre of great industrious nations, they have lost their relish for war, and consider it as a terrible calamity; they cherish the minister who gives them peace, and abhor the one who drives them into unnecessary wars. Their local disputes, which used to be settled by the sword, are now referred to the tribunals of the country. They have substituted a moral to a physical force. They have changed the habits of plunder for those of industry; and they find themselves richer and happier for the change.

Who will say that the progress of society will stop short in the present stage of its career? that great communities will not discover a mode of arbitrating their disputes, as little ones have done? that nations will not lay aside their present ideas of independence and rivalship, and find themselves more happy and more secure in one great universal society, which shall contain within itself its own principles of defence, its own permanent security? It is evident that national security, in order to be permanent, must be founded on the moral force of society at large, and not on the physical force of each nation independently exerted. The ultima ratio must not be a cannon, but a reference to some rational mode of decision worthy of rational beings.