cannot at will call up any idea that is not connected with the train.* But a train of ideas fuggested by read ing, may be varied at will, provided we have books at hand. The power that nature hath given us over our train of perceptions may be greatly ftrengthened by proper difcipline, and by an early application to bufinefs; witness fome mathematicians, who go far beyond common nature in flownefs and uniformity and still more perfons devoted to religious exercifes, who pafs whole days in contemplation, and impofe upon themselves long and fevere penances. With respect to celerity and variety, it is not eafily conceived what length a habit of activity in affairs will carry fome men. Let a ftranger, or let any perfon to whom the fight is not familiar, attend the chancellor of Great Britain through the labours but of one day, during a feffion of parliament: how great will be his aftonishment! what multiplicity of lawbufinefs, what deep thinking, and what elaborate application to matters of government! The train of perceptions must in that great man be accelerated far beyond the ordinary courfe of nature; yet no confufion or hurry; but in every article the greatest order and accuracy. Such is the force of habit. How happy is man, to have the command of a principle of action that can elevate him fo far above the ordinary condition of humanity!†

We are now ripe for confidering a train of perceptions, with refpect to pleasure and pain: and to that fpeculation peculiar attention must be given, be cause it ferves to explain the effects that uniformity

* See chap. t.

This chapter was compofed in the year 1763. ¦

and

and variety have upon the mind. A man, when his perceptions flow in their natural courfe, feels himself free, light, and eafy, especially after any forcible acceleration or retardation. On the other hand, the accelerating or retarding the natural courfe, excites a pain, which, though fcarcely felt in small removes, becomes confiderable toward the extremes. Averfion to fix on a fingle object for a long time, or to take in a multiplicity of objects in a short time, is remarkable in children; and equally fo in men unaccustomed to bufinefs: a man languifhes when the fucceffion is very flow; and, if he grow not impatient, is apt to fall asleep: during a rapid fucceffion, he hath a feeling as if his head were turning round; he is fatigued, and his pain resembles that of weari nefs after bodily labour.

But a moderate courfe will not fatisfy the mind, unless the perceptions be alfo diverfified: number without variety is not fufficient to conftitute an agree able train. In comparing a few objects, uniformity is pleafant; but the frequent reiteration of uniform objects becomes unpleasant: one tires of a scene that is not diverfified; and foon feels a fort of unnatural reftraint when confined within a narrow range, whether occafioned by a retarded fucceffion or by too great uniformity. An excefs in variety is, on the other hand, fatiguing: which is felt even in a train of related perceptions; much more of unrelated perceptions, which gain not admittance without effort the effort, it is true, is fcarce perceptible in a single instance; but by frequent reiteration it becomes exceedingly painful. Whatever be the cause, the fact is certain, that a man never finds himself more at cafe, than when his perceptions fucceed each other with a certain degree, not only of velocity, but also of variety. The pleasure that arifes from a train

of

of connected ideas, is remarkable in a reverie; efpecially where the imagination interpofeth, and is active in coining new ideas, which is done with wonderful facility: one must be fenfible, that the ferenity and ease of the mind in that state, makes a great part of the enjoyment. The cafe is different where external objects enter into the train; for these, making their appearance without order, and without connection fave that of contiguity, form a train of perceptions that may be extremely uniform or extremely diverfified; which, for opposite reasons, are both of them painful.

To alter, by an act of will, that degree of variety which nature requires, is not lefs painful, than to alter that degree of velocity which it requires. Contemplation, when the mind is long attached to one fubject, becomes painful by restraining the free range of perception: curiofity, and the profpect of useful discoveries, may fortify one to bear that pain: but it is deeply felt by the bulk of mankind, and produceth in them averfion to all abstract sciences. In any profeffion or calling, a train of operation that is fimple and reiterated without intermiffion, makes the operator languish, and lofe vigor: he complains neither of too great labour, nor of too little action; but regrets - the want of variety, and the being obliged to do the fame thing over and over: where the operation is fufficiently varied, the mind retains its vigor, and is pleased with its condition. Actions again create uneafinefs when exceffive in number or variety, though in every other respect pleasant: thus a throng of bufinefs in law, in phyfic, or in traffic, diftreffes and diftracts the mind, unless where a habit of application is acquired by long and conftant exercife: the exceffive variety is the diftreffing circumstance; and the mind fuffers grievously by being kept constantly upon the stretch.

With

With relation to involuntary caufes disturbing that degree of variety which nature requires, a flight pain affecting one part of the body without variation, "becomes, by its conftancy and long duration, almost infupportable: the patient, fenfible that the pain is not increafed in degree, complains of its conftancy more thanof its feverity, of its engroffing his whole thoughts, and admitting no other object. "A fhifting pain is more tolerable, because change of place contributes to va◄ riety and an intermitting pain, fuffering other ob jects to intervene, ftill more fo. Again, any fingle colour or found often returning becomes unpleafant ; as may be obferved in viewing a train of fimilar apartments in a great houfe painted with the fame colour, and in hearing the prolonged tollings of a bell. Col our and found varied within certain limits, though without any order, are pleafant; witnefs the various colours of plants and flowers in a field, and the va rious notes of birds in a thicket: increafe the num ber or variety, and the feeling. becomes unpleafant ; thus a great variety of colours, crowded upon a fmall canvas or in quick fucceffion, create an uneafy feeling, which is prevented by putting the colours at a greater diftance from each other either of place of of time. A number of voices in a crowded affembly, a number of animals collected in a market, produce an unpleafant feeling; though a few of them together, or all of them in a moderate fucceffion, would be pleafant. And because of the fame excess in variety, a number of pains felt in different parts of the body, at the fame inftant or in a rapid fucceffion, are an exquisite torture.

The pleasure or pain refulting from a train of perceptions in different circumftances, are a beautiful contrivance of nature for valuable purposes. But being fenfible, that the mind, inflamed with fpecula

go

tions fo highly interesting, is beyond meafure difpofed to conviction; I fhall be watchful to admit no argument nor remark, but what appears folidly founded: and with that caution I proceed to unfold these purpofes. It is occafionally obferved above, that perfons of a phlegmatic temperament, having a sluggish train of perceptions are indifpofed to action; and that activity constantly accompanies a brisk flow of percep tions. To afcertain that fact, a man need rot abroad for experiments: reflecting on things paffing in his own mind, he will find, that a brisk circulation of thought conftantly prompts him to action; and that he is averfe to action when his perceptions languifh in their courfe. But as man by nature is formed for action, and must be active in order to be happy, nature hath kindly provided against indolence, by annexing pleasure to a moderate courfe of percep tions, and by making any remarkable retardation painful. A flow courfe of perceptions is attended with another bad effect: man, in a few capital cafes, is governed by propenfity or inftinct; but in matters that admit deliberation and choice, reafon is affigned him for a guide: now as reafoning requires often a great compafs of ideas, their fucceffion ought to be fo quick as readily to furnish every motive that may be neceffary for mature deliberation; in a languid fuc ceffion, motives will often occur after action is commenced when it is too late to retreat.

Nature hath guarded man, her favourite, against a fucceffion too rapid, no lefs carefully thran against one too flow: both are equally painful, though the pain is not the fame in both. Many are the good effects of that contrivance. In the firft place, as the exertion of bodily faculties is by certain painful fenfations confined within proper limits, Nature is equal. ly provident with refpect to the nobler faculties of

the