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Cato's Letter No. 122

Inquiry concerning the Operations of the Mind of Man, and those of other Animals.

John Trenchard (Saturday, March 30, 1723)

SIR, The world has always run riot after one whimsy or another. Astrology was the madness of the last age: Pretended prophets, fortune-tellers, conjurers, witches, apparitions, and such-like superstitious fooleries, have been in request in all ages. Dreamers of dreams led, misled, and governed mankind, for more than two thousand years together; and they are far from being out of fashion yet: And it is no small comfort, that this sort of divination, and instruction is left to us: for I do not find, that any society of men pretend to any jurisdiction over sleeping dreams, or to have the sole conduct, regulation, or interpretations of them; but every man, when he is asleep, is left at liberty to dream as he can, and to interpret his dreams as he thinks fit; which indulgence is not allowed to our waking dreams. I shall therefore take the advantage of this present toleration of dreaming, to dream too; and though I will not vouch or be answerable for the truth of my dreams, yet I dare compare them with those of the ancient and some modern philosophers.

I conceive, that the divines of all religions have ever agreed, that the soul of man is a being separate from the body, and in its own nature capable of subsisting independent of it. I also conceive, that all Christian divines hold, or ought to hold, that it is a distinct being from what we call the mind, and superadded to it by the divine goodness, to distinguish mankind from the brute creation, to continue his being after the dissolution of the body, and to make him an object of future rewards and punishments. For it is certain, that other animals have minds too; that they reason and resolve, though in an inferior degree to ourselves; and I think also, that it is almost universally agreed, that those minds take the fate of their bodies, and die with them.

The philosophers of all ages have set themselves to work, and employed their wits, to trace the minds of brutes to their first sources or principles, and so to account for their operations; but have differed as widely as they do in other matters about which they know nothing. Some have supposed them to be modifications of matter and motion, and operations resulting from the organization and mechanism of the body, like the striking of a clock, or watch, or musick made by blowing into or striking upon an instrument; for as the percussion of one body against another makes sound, so the instruments or vehicles upon which or through which it hits or passes, modify and determine the species of it.

These endeavour to illustrate the power of voluntary motion (namely, how a sudden impulse of the will can set a great machine in action) by what they think is analogous to it in mechanical obervations: As for instance, a little agitation of the air will turn a windmill, or sail a great ship; and it is demonstrable in mechanicks, that a hair of a manís head, or a puff of his breath, by the help of proper springs, wheels, and pulleys, may have force enough to move a body as big and heavy as the world. Then they reason, that if the little contrivance and trifling experiments which we can make of the powers of matter and motion can convince us of its capacity to produce such surprizing effects and operations, a machine organized by the excellent skill and most wise contrivance of the Supreme Architect, consisting too of such subtle animal spirits, and of such infinite springs, wheels, and tubes, must have suitable operations, some of them such as are not perceivable by our senses, or penetrable by our capacities. They conceive, that there is something in vegetation analogous to animal life; and that the difference of the appearing sensations between the highest vegetable and the lowest animal (as for example, between the sensitive plant and worm or snail) is so very little, that they can account for them both by the same system of reasoning; or rather, they are both equally unaccountable by our reason: And therefore, since the former is undoubtedly only a modus or operation of matter and motion they think that we cannot know but the other may be so too.

Many pretenders to philosophy have thought the mind of a brute animal to be part of the body, originally formed with it, and differing only from the other parts, as it has a finer contexture, and consists of more subtle and volatile particles of matter, that cannot keep together without their case or shell, and consequently cannot exist together in a separate state from the body; but when the organization and mechanism of its inclosure is dissolved or broken to pieces, it must dissipate into the mass of matter again.

But the greater number have thought, that there is an anima mundi, or universal spirit, that permeates and actuates all matter, and is the source of vegetable and animal life; which spirit receiving its modification from, and assimilating itself to, the nature and structure of the body through which it passes, or in which it acts, constitutes all the specific effects and operations which we daily see, feel, and admire; as in the instances before given, the same wind, blown into different instruments, makes different kinds of musick.

Many of this latter sort have fancied, that all nature is full of organized bodies, with each a particular and sufficient portion of this universal and vital spirit annexed to or inherent in them; which bodies being in constant motion, fall gradually into peculiar matrixes or wombs, which are necessary to bring them to perfection. They think that the first seeds of all vegetables and animals (which are indeed the vegetables and animals themselves) must have been formed at the creation of the world; that the seeds of the former must make their progression through the veins and tubes of the vegetables of the same kind, to prepare them to become fruit, and to produce that grosser sort of seed which more easily, and by another motion, grows into the same kind of plant or tree again; and that those of the latter must pass through the body of the male to awaken the first life of those who are sent to be nursed in the eggs of the female for increase and expansion; and they conceive, that experience confirms this opinion; for that an egg will not produce an animal, till the male has thrown one into it; but afterwards, by the assistance of that vital warmth which it receives from a living body (or that heat which is equivalent to it, and is necessary to preserve the tender fibres and juices of infant animals) it continues life, nourishes and increases it, till it swell and break out of its first inclosure, and be strong enough to receive grosser nourishment.

It seems to me, that the generation or production of vegetables is analogous to, if not the same with, that of animals, and that they both receive their first nourishment and increase in eggs; and what are vulgarly called the seeds of the former, are eggs, that inclose the minute specks of entity, which are its original seeds or principles, or rather the whole plants or trees in miniature, nourish them for some time, and defend them against the injuries of exterior bodies, when they first expand themselves, and swell out of their native beds, and their tender parts become susceptible of outward violence. It is evident, that if we break up new or maiden ground, many sorts of vegetables will spontaneously arise, which have undoubtedly their proper seeds in the earth, and as undoubtedly none of those gross seeds which produce the same plant again; and it is plain, that the latter are subject to be destroyed by exterior accidents, and to decay and die; which the others are not, but very probably have had an unmolested existence from the beginning of time, and would have continued in their first state, if they had not received a fermentation, and found a proper matrix, by the opening the fibres and bowels of the earth; which matrix must be different from what multiplies the same species afterwards.

There have been other sects of philosophers (if folly may be called by that name) who have distinguished themselves by supposing the mind and soul to be the same being, and consequently enjoyed in common by other animals, as well as men; and they have supposed this being not only to be different too from the body, and capable in its own nature, not only of subsisting independent of it, but believed that it received prejudice, and was restrained from the free use of many of its faculties, by its imprisonment and union with the body; and yet, when it was discharged from its gaol, was at liberty, capable or obliged to enter into some other organized body, to animate it, and to perform the functions of it. This was the opinion of the transmigrators of souls formerly, but is justly rejected by very many Christians; is contrary to revelation, and would put brute animals upon a level with mankind: for it cannot be denied that other living creatures have minds, and as certainly no souls; nor are they capable of just or unjust actions, or of receiving future rewards and punishments due to those actions.

It is certain that they have minds, and consequently thought; reflection upon past actions, or memory; sensations of pleasure and pain; and in many instances they judge well of their own interests, and choose proper means to attain them: And mankind have not only the above qualities in common with them, but possess them in a greater degree; and over and above enjoy, by the bounty of heaven, immortal souls, capable of continuing their duration to all eternity; of which some traces are discoverable in our nature, and the rest are ascertained to us by revelation, which man alone is capable of receiving: But how this superadded being operates upon and controls the actions of the mind and body, we seem to be wholly in the dark; but it is certain that in some respects they are all blended together, co-operate, and act as one being; and therefore are answerable for their joint actions, and are to take the same fate at last, when they come to be united again. However, in this discourse it may be proper to consider them separately, and not to impute the mechanical operations of matter and motion immediately to our immortal part; especially in such instances as are the same, or analogous to the actions of brutes, who are wholly mortal.

Therefore, if we consider this energy, or principle, called mind, as separate from an human soul, we shall find, that it mingles with, animates, and informs the bodies of men, and of all animals; and whether it be only a modification of matter and motion, whether subtle, volatile, and elastick particles of matter, called animal spirits; whether it be elementary fire, or what the ancients called anima mundi, or divinae particula aurae, that is, a particle of the soul of the universe, or a spark or impulse of the divinity; or whatever else it be unknown to us; it is most certain, that its power and action over some sorts of organized bodies is very surprizing, and not to be accounted for by any other system of matter and motion which falls within our comprehensions; nor can I conceive it possible that it ever should be: For how should any being trace its own principles, and the causes which gave it being, know what it was before it was, or be able to think how it came to think, unless by resolving all thinking into the power of its creator? To know the modus of creation is the next step to creation, and to a creatureís creating itself, or another being like itself, and rendering the opus operatum, or the work performed, equally or near as valuable as the artificer.

The powers of this principle are very stupendous. We seem to owe to this most, if not all our sensations, appetites, affections, and passions, which obviously receive constant alteration by the addition of new and adventitious particles of matter, which must more or less be penetrated and inspired with this spirit, which unites to what is called the mind, as the grosser parts do to the body; for neither can grow but by addition, or be lessened but by subtraction, though their actions may be, and are often clogged by internal and external impediments. Our desires and fears, which appear to direct, and indeed comprehend, all the actions of the mind, are only passions, or perturbations of it, made by the impressions of external and internal causes; and what we call judgment seems to me to be no more than a struggle of those passions, or, in other words, the balance of the conveniences or inconveniences which will result from what we desire or fear, and the heavier scale must weigh down.

When a proper proportion of this active force is duly diffused through the whole machine, it will equally receive or resist the impressions of objects; the passions will be alike balanced, and consequently our thoughts and actions will be regular, and what we call prudent: But if there be too little to animate the mass, or if it meet such obstructions as hinder its energy, it becomes stupidity or folly; but if it abound, and overinform its tenement, or if it be unequally dispersed, or put or kept out of its proper place by natural or accidental obstructions, it causes indiscretion, extravagance, and, in a greater degree, madness. Of which several manners of thinking there are as many kinds and degrees as there are irregularities in manís conduct; and I doubt there are few men so equally tempered, but they have, at different times, more or less of all these qualities by the unequal supplies of this vital spirit, or by the occasional obstructions which it meets with. When we denominate a man mad, or a fool, we mean only that he is more so than most others of his species; for all men at times have a mixture of both, and no menís actions will always bear the test of just reasonings, and if we could enter and look into their private thoughts, I doubt they would much less do so. All sudden passion is temporary madness, as continued passion is continued madness; and all want of apprehension is folly.

Madness too is undoubtedly to be learned and acquired by habit and exercise, as well as covetousness, pride, ambition, love, desire of revenge, and other qualities: All which, carried beyond a certain degree, become madness; as every thing else is, when menís desires or fears, or the means chosen to attain the one, or avoid the other, are extravagant, and above human power or prudence. Nor does madness (as has been said) depend only upon wrong organizations at first, or upon the original ill temperament of the juices, by an undue mixture or superabundance of this active spirit; but often upon the fortuitous alterations which both receive afterwards by diet, physick, action, or accidents: for when those volatile particles have been long diverted, and used to run in wrong and indirect channels, the proper ones will be closed up, and they will have no others but the wrong ones to go in; which unequal distribution must overload some, and starve the rest, and make their operations as heterogeneous and irregular as their causes are; and daily experience shews, that men who have been long used to think or act only in one way, are very difficultly, if ever, put into another.

But of all the several species or kinds of madness in the world, none is so flagrant, catching, and mischievous, as the madness of enthusiasm; which is still the worse, as it adopts and puts on the mask and appearance of zeal, and often passes for sobriety and inspiration; and consequently is incapable of a cure, because it will not seek or accept a remedy. This shall be the subject of my next two papers; and then my dream will be out.

T I am, &c.

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