learn from daily experience, that a train of thought is not merely cafual. And if it depend not upon will, nor upon chance, we must try to evolve by what law it is governed. The fubject is of importance in the science of human nature; and I promise beforehand, that it will be found of great importance in the fine arts.

It appears that the relations by which things are linked together, have a great influence in directing the train of thought; and we find by experience, that objects are cannected in the mind precifely as they are externally. Beginning then with things external, we find that they are not more remarkable by their inherent properties' than by their various relations. We cannot any where extend our view without perceiving things connected together by certain relations. One thing perceived to be a caufe, is connected with its feveral

We cannot form a conception of fuch a thing. This argument appears to me fatisfactory: if it need confirmation, I urge experience. Whoever makes a trial will find, that objects are linked together in the mind, forming a connected chain; and that we have not the command of any object independent of the chain.

effects;

effects; fome things are connected by contiguity in time, others by contiguity in place; fome are connected by refemblance, some by contraft; fome go before, fome follow. Not a fingle thing appears folitary, and altogether devoid of connection. The only difference is, that fome are intimately connected, fome more flightly; fome near, fome at a distance.

Experience as well as reafon may fatisfy us, that the train of mental perceptions is in a great measure regulated by the foregoing relations. Where a number of things are linked together, the idea of any one fuggefts the reft; and in this manner is a train of thoughts compofed. Such is the law of fucceffion; whether an original law, or whether directed by fome latent principle, is doubtful; and probably will for ever remain fo. This law, however, is not inviolable. It fometimes happens, though rarely, that an idea presents itself to the mind without any connection, fo far at least as can be discovered..

But though we have not the abfolute command of ideas, yet the Will hath a confiderable

fiderable influence in directing the order of connected ideas. There are few things but what are connected with many others. By this means, when any thing becomes an object; whether in a direct furvey, or ideally only, it generally fuggefts many of its connections. Among these a choice is afforded. We can infist upon one, rejecting others; and we can even infist upon what has the flightest connection. Where ideas are left to their natural course, they are generally continued through the strongest connections. The mind extends its view to a fon more readily than to a fervant, and more readily to a neighbour than to one living at a distance. This order may be varied by Will, but ftill within the limits of connected objects. In fhort, every train of ideas must be a chain, in which the particular ideas are linked to each other. We may vary the order of a natural train; but not fo as to diffolve it altogether, by carrying on our thoughts in a loofe manner without any connection. So far doth our power extend; and that for all useful purposes.

power is fufficient To give us more power,

power, would probably be detrimental instead of being falutary.

Will is not the only cause that prevents a train of thought from being continued through the strongest connections. Much depends on the present tone of mind; for a fubject that accords with this tone is always welcome. Thus, in good fpirits, a chearful fubject will be introduced by the flighteft connection; and one that is melancholy, not lefs readily in low fpirits. Again, an interesting fubject is recalled, from time to time, by any connection indifferently, ftrong or weak. This is finely touched by Shakespear, with relation to a rich cargo

at fea.

My wind, cooling my broth,

Would blow me to an ague, when I thought
What harm a wind too great might do at fea.
I fhould not fee the fandy hour-glafs run,
But I fhould think of fhallows and of flats;
And fee my wealthy Andrew dock'd in fand,
Vailing her high top lower than her ribs,
To kifs her burial. Should I go to church,
And fee the holy edifice of stone,

And not bethink me ftrait of dangerous rocks?

VOL. I.

D

Which

Which touching but my gentle veffel's fide,
Would scatter all the fpices on the stream,
Enrobe the roaring waters with my filks;
And, in a word, but now worth this,
And now worth nothing.

Merchant of Venice, a&t 1. fc. 1.

Another cause clearly distinguishable from that now mentioned, hath also a confiderable influence over the train of ideas. In fome minds of a fingular frame, thoughts and circumstances crowd upon each other by the flightest connection. I afcribe this to a defect in the faculty of difcernment. A person who cannot accurately distinguish betwixt a flight connection and one that is more folid, is equally affected with both. Such a perfon must neceffarily have a great command of ideas, because they are introduced by any relation indifferently; and the flighter relations, being without number, must furnish ideas without end. This doctrine is, in a lively manner, illuftrated by Shakespear.

Falstaff. What is the grofs fum that I owe thee?
Hoftefs. Marry, if thou wert an honest man,

thyfelf