A

MAN, while awake, is conscious of a continued train of perceptions and ideas paffing in his mind. It requires no activity on his part to carry on the train: nor can he at will add any idea to the train *. At the fame time, we learn from daily experi

* For how fhould this be done? what idea is it that we are to add? If we can fpecify the idea, that idea is already in the mind, and there is no occafion for any act of the will. If we cannot specify any idea, I next demand, how can a perfon will, or to what purpose, if there be nothing in view? We cannot form a conception of fuck a thing. If this argument need confirmation, I urge experience whoever makes a trial will find, that ideas are linked together in the mind, forming a connected chain; and that we have not the command of any idea independent of the chain.

VOL. I.

B

ence,

ence, that the train of our thoughts is not regulated by chance: and if it depend not upon will, nor upon chance, by what law is it governed? The question is of importance in the science of human nature; and I promise before hand, 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. Taking a view of external objects, their inherent properties are not more remarkable, than the various relations that connect them together: Cause and effect, contiguity in time or in place, high and low, prior and pofterior, refemblance, contraft, and a thoufand other relations, connect things together without end. 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 will fatisfy us of what reafon makes probable, that the train of our thoughts is in a great measure regulated by the foregoing relations an external object is no fooner presented to us in idea, than it fuggefts to the mind other objects to which it is related; and in that manner is a train of thoughts compofed. Such is the law of fucceffion; which must be natural, because it governs all human beings. The law, however, feems not to be inviolable: it fometimes happens that an idea arifes in the mind,

without

without any perceived connection; as, for example, after a profound fleep.

But, though we cannot add to the train an unconnected idea, yet in a measure we can attend to fome ideas, and difmifs others. There are few things but what are connected with many others; and, when a thing thus connected becomes a fubject of thought, it commonly fuggefts many of its connections: among thefe a choice is afforded; we can infift upon one, rejecting others; and fometimes we infift on what is commonly held the flighter connection. Where ideas are left to their natural course, they are continued through the ftricteft 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, as obferved, may be varied by will, but ftill within the limits of related objects; for though we can vary the order of a natural train, we cannot diffolve the train altogether, by carrying on our thoughts in a loofe manner without any connection. So far doth our power extend; and that power is fufficient for all useful purpofes to have more power, would probably be hurtful, instead of being falutary.

Will is not the only cause that prevents a train of thought from being continued through the ftricteft connections: much depends on the prefent tone of mind: for a fubject that accords with that tone is always welcome. Thus, in good fpirits,

B 2

spirits, a chearful fubject will be introduced by the flightest connection; and one that is melancholy, no lefs readily in low fpirits: an interesting fubject is recalled, from time to time, by any connection indifferently, ftrong or weak; which 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 sea.
I should not fee the fandy hour-glass 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?
Which touching but my gentle veffel's fide,
Would fcatter all the fpices on the ftream,
Enrobe the roaring waters with my filks;
And, in a word, but now worth this,

And now worth nothing.

Merchant of Venice, act 1. fc. 1.

Another cause clearly diftinguishable from that now mentioned, hath also a confiderable influence to vary the natural train of ideas ; which is, that, in the minds of fome perfons, thoughts and circumftances crowd upon each other by the flighteft connections. I afcribe this to a bluntness in the difcerning faculty; for a perfon who cannot accurately distinguish be

tween