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 an uneafinefs when exceffive in number or variety, though in every other respect agreeable: thus a throng of business in law, in physick, or in traffick, diftreffes and diftracts the mind, unless where a habit of application is acquired by long and conftant exercife: the exceffive variety is the diftreffing circumftance; and the mind fuffers grievously by being kept conftantly upon the ftretch.

With relation to involuntary causes 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 than of its feverity, of its ingroffing his whole thoughts, and admitting no other object. A shifting pain is more tolerable, becaufe change of place contributes to yariety and an intermitting pain, fuffering other objects to intervene, still more fo. Again, any fingle colour or found often returning, becomes difagreeable; as may be observed in viewing a train of similar apartments painted with the fame colour, and in hearing the prolonged tollings of a bell, Colour and found varied within cer

tain limits, though without any order, are agreeable; witnefs the various colours of plants and flowers in a field, and the various notes of birds in a thicket: increase the number or variety, and the feeling becomes unpleasant; thus a great variety of colours, crowded upon a small canvas or in quick fucceffion, create an uneafy feeling, which is prevented by putting the colours at a greater distance either of place or of time. A number of voices in a crowded affembly, a number of animals collected in a market, produce an unpleasant feeling; though a few of them together, or all of them in a moderate fucceffion, would be pleasant. And because of the fame excefs in variety, a number of pains felt in different parts of the body, at the fame inftant or in a rapid fucceffion, make an exquifite tor

ture.

The foregoing doctrine concerning the train of perceptions, and the pleasure or pain refulting from that train in different circumstances, will be confirmed by attending to the final caufe of these effects. And being fenfible, that the mind, inflamed with fpeculations of this kind fo highly interefting, is beyond meafure difpofed to conviction; I fhall be watchful to admit no argument nor remark, but what appears folidly founded; and with this caution I proceed to the inquiry. It is occafionally obferved above, that perfons of a phlegmatic temperament, having a sluggish train of perceptions, are indifpofed to action; and

and that activity conftantly accompanies a brisk
motion of perceptions. To afcertain this fact, a
man need not go abroad for experiments re-
flecting upon things paffing in his own mind, he
will find, that a brifk circulation of thought con-
stantly prompts him to action; and that he is a-
verfe to action when his perceptions languifh in
their courfe. But man by nature is formed for
action, and he must be active in order to be hap-
Nature therefore hath kindly provided a-
py.
gainst indolence, by annexing pleasure to a mo-
derate course of perceptions, and by making e-
very remarkable retardation painful. A flow
courfe of perceptions, is attended with another
bad effect: man, in a few capital cafes, is governed
by propensity or inftinct; but in matters that ad-
mit deliberation and choice, reafon is affigned
him for a guide: now, as reafoning requires of-
ten a great compafs of ideas, their fucceffion
ought to be fo quick, as readily to furnish every
motive that may be neceffary for mature delibe-
ration; in a languid fucceffion, motives will of-
ten occur after action is commenced, when it is
too late to retreat.

Nature hath guarded man, her favourite, against a fucceffion too rapid, not lefs carefully than against one too flow: both are equally painful, though the pain is not the fame in both. Many are the good effects of this contrivance. In the first place, as the bodily faculties are by certain painful fenfations confined within proper

limits,

limits, beyond which it would be dangerous to ftrain the tender organs, Nature, in like manner, is equally provident with refpect to the nobler faculties of the mind: thus the pain of an accelerated courfe of perceptions, is Nature's admonition to relax our pace, and to admit a more gentle exertion of thought. Another valuable purpose may be gathered, from confidering in what manner objects are imprinted on the mind to make an impreffion fuch as to give the memory fast hold of the object, time is required, even where attention is the greatest; and a moderate degree of attention, which is the common cafe, must be continued ftill longer to produce the fame effect: a rapid fucceffion, then, muft prevent objects from making impreffions fo deep as to be of real fervice in life: and Nature accordingly, for the fake of memory, has by a painful feeling guarded against a rapid fucceffion. But a still more valuable purpose is anfwered by this contrivance: as, on the one hand, a fluggish course of perceptions indifpofeth to action; fo, on the other, a courfe too rapid impels to rafh and precipitant action: prudent conduct is the child of deliberation and clear conception, for which there is no place in a rapid course of thought. Nature therefore, taking measures for prudent conduct, has guarded us effectually from precipitancy of thought, by making it painful.

Nature not only provides against a fucceffion too flow or too quick, but makes the middle

courfe

course extremely pleafant. Nor is this middle courfe confined within narrow bounds: every ¿ man can naturally, without pain, accelerate or retard in fome degree the rate of his perceptions. And he can do this in a still greater degree by the force of habit a habit of contemplation annihilates the pain of a retarded courfe of perceptions; and a busy life, after long practice, makes acceleration pleasant.

:

Concerning the final caufe of our taste for va riety, it will be considered, that human affairs, complex by variety as well as number, require the distributing our attention and activity in meafure and proportion. Nature therefore, to fecure a juft diftribution correfponding to the variety of human affairs, has made too great uniformity or too great variety in the course of our perceptions, equally unpleafant and indeed, were we addicted to either extreme, our internal conftitution would be ill fuited to our external circumftances. At the fame time, where great uniformity of operation is required, as in feveral manufactures, or great variety, as in law or phyfic, Nature, attentive to all our wants, hath also provided for thefe cafes, by implanting in the breast of every perfon, an efficacious principle, which leads to habit: an obftinate perfeverance in the fame occupation, relieves us from the pain of exceffive uniformity; and the like perfeverance in a quick circulation of different occupations, relieves us from the pain of exVOL.I. U

ceffive