Excerpts From the Life and Letters of John Locke

Supplement 1

The knowledge we acquire in this world I am apt to think extends not beyond the limits of this life. The beatific vision of the other life needs not the help of this dim twilight; but be that as it will, I am sure the principal end why we are to get knowledge here, is to make use of it for the benefit of ourselves and others in this world;

but if by gaining it we destroy our health, we labour for a thing that will be useless in our hands; and if by harassing our bodies (though with a design to render ourselves more useful) we deprive ourselves of the abilities and opportunities of doing that good we might have done with a meaner talent, which God thought sufficient for us by having denied us the strength to improve it to that pitch which men of stronger constitutions can attain to, we rob God of so much service, and our neighbour of all that help which, in a state of health, with moderate knowledge, we might have been able to perform. He that sinks his vessel by overloading it, though it be with gold and silver and precious stones, will give his owner but an ill account of his voyage.

It being past doubt, then, that allowance is to be made for the temper and strength of our bodies, and that our health is to regulate the measure of our studies, the great secret is to find out the proportion; the difficulty whereof lies in this, that it must not only be varied according to the constitution and strength of every individual man, but it must also change with the temper, vigour, and circumstances, and health of every particular man, in the different varieties of health,

or indisposition of body, which everything our bodies have any commerce with is able to alter: so that it is as hard to say how many hours a day a man shall study constantly, as to say how much meat he shall eat every day, wherein his own prudence, governed by the present circumstances, can only judge. . . The regular proceeding of our watch not being the fit measure of time, but the secret motions of a much more curious engine, our bodies being to limit out the portion of time in this occasion: however,

it may be so contrived that all the time may not be lost, for the conversation of an ingenious friend upon what one hath read in the morning, or any other profitable subject, may perhaps let into the mind as much improvement of knowledge, though with less prejudice to the health, as settled solemn poring over books, which we generally call study; which, though a necessary part, yet I am sure is not the only, and perhaps not the best, way of improving the understanding.

2. Great care is to be taken that our studies encroach not upon our sleep: this I am sure, sleep is the great balsam of life and restorative of nature, and studious sedentary men have more need of it than the active and laborious, because those men's business and their bodily labours, though they waste their spirits, help transpiration, and carry away their excrements,

which are the foundation of diseases; whereas the studious sedentary man, employing his spirits within, equally or more wastes them than the other, but without the benefit of transpiration, allowing the matter of disease insensibly to accumulate. We are to lay by our books and meditations when we find either our heads or stomachs indisposed upon any occasion; study at such time doing great harm to the body, and very little good to the mind.

1st. As the body, so the mind also, gives laws to our studies; I mean, to the duration and continuance of them; let it be never so capacious, never so active, it is not capable of constant labour nor total rest. The labour of the mind is study, or intention of thought, and when we find it is weary, either in pursuing other men's thoughts, as in reading, or tumbling or tossing its own, as in meditation, it is time to give off and let it recover itself.

Sometimes meditation gives a refreshment to the weariness of reading, and vice versâ; sometimes the change of ground, i. e. going from one subject or science to another, rouses the mind, and fills it with fresh vigour; oftentimes discourse enlivens it when it flags, and puts an end to the weariness without stopping it one jot, but rather forwarding it in its journey; and sometimes it is so tired, that nothing but a perfect relaxation will serve the turn. All these are to be made use of according as every one finds most successful in himself to the best husbandry of his time and thought.

2nd. The mind has sympathies and antipathies as well as the body; it has a natural preference often of one study before another. It would be well if one had a perfect command of them, and sometimes one is to try for the mastery, to bring the mind into order and a pliant obedience; but generally it is better to follow the bent and tendency of the mind itself, so long as it keeps within the bounds of our proper business, wherein there is generally latitude enough. By this means, we shall go not only a great deal faster, and hold out a great deal longer,

but the discovery we shall make will be a great deal clearer, and make deeper impressions in our minds. The inclination of the mind is as the palate to the stomach; that seldom digests well in the stomach, or adds much strength to the body, that nauseates the palate, and is not recommended by it.

There is a kind of restiveness in almost every one's mind; sometimes, without perceiving the cause, it will boggle and stand still, and one cannot get it a step forward; and at another time it will press forward, and there is no holding it in. It is always good to take it when it is willing, and keep on whilst it goes at ease, though it be to the breach of some of the other rules concerning the body.

But one must take care of trespassing on that side too often, for one that takes pleasure in study, flatters himself that a little now, and a little to-morrow, does no harm, that he feels no ill effects of an hour's sitting up,-insensibly undermines his health, and, when the disease breaks out, it is seldom charged to these past miscarriages that laid in the provision for it.

The subject being chosen, the body and mind being both in a temper fit for study, what remains but that a man betake himself to it? These certainly are good preparatories, yet if there be not something else done, perhaps we shall not make all the profit we might.

1st. It is a duty we owe to God, as the fountain and author of all truth, who is truth itself; and it is a duty also we owe our own selves, if we will deal candidly and sincerely with our own souls; to have our minds constantly disposed to entertain and receive truth wheresoever we meet with it, or under whatsoever appearance of plain or ordinary, strange, new, or perhaps displeasing, it may come in our way. Truth is the proper object, the proper riches and furniture of the mind,

and according as his stock of this is, so is the difference and value of one man above another. He that fills his head with vain notions and false opinions, may have his mind perhaps puffed up and seemingly much enlarged, but in truth it is narrow and empty; for all that it comprehends, all that it contains, amounts to nothing, or less than nothing; for falsehood is below ignorance, and a lie worse than nothing.

Our first and great duty then is, to bring to our studies and to our inquiries after knowledge a mind covetous of truth; that seeks after nothing else, and after that impartially, and embraces it, how poor, how contemptible, how unfashionable soever it may seem.

This is that which all studious men profess to do, and yet it is that where I think very many miscarry. Who is there almost that has not opinions planted in him by education time out of mind; which by that means come to be as the municipal laws of the country, which must not be questioned, but are then looked on with reverence as the standards of right and wrong, truth and falsehood; when perhaps these so sacred opinions were but the oracles of the nursery, or the traditional grave talk of those who pretend to inform our childhood; who receive them from hand to hand without ever examining them?

This is the fate of our tender age, which being thus seasoned early, it grows by continuation of time, as it were, into the very constitution of the mind, which afterwards very difficultly receives a different tincture. When we are grown up, we find the world divided into bands and companies; not only as congregated under several polities and governments, but united only upon account of opinions, and in that respect combined strictly one with another,

and distinguished from others, especially in matters of religion. If birth or chance have not thrown a man young into any of these, which yet seldom fails to happen, choice, when he is grown up, certainly puts him into some or other of them; often out of an opinion that that party is in the right, and sometimes because he finds it is not safe to stand alone, and therefore thinks it convenient to herd somewhere.

Now, in every one of these parties of men there are a certain number of opinions which are received and owned as the doctrines and tenets of that society, with the profession and practice whereof all who are of their communion ought to give up themselves, or else they will be scarce looked on as of that society, or at best be thought but lukewarm brothers, or in danger to apostatize.

It is plain, in the great difference and contrariety of opinions that are amongst these several parties, that there is much falsehood and abundance of mistakes in most of them. Cunning in some, and ignorance in others, first made them keep them up; and yet how seldom is it that implicit faith, fear of losing credit with the party or interest (for all these operate in their turns),

suffers any one to question the tenet of his party; but altogether in a bundle he receives, embraces, and, without examining, he professes and sticks to them, and measures all other opinions by them. Worldly interest also insinuates into several men's minds divers opinions, which, suiting with their temporal advantage, are kindly received, and in time so riveted there, that it is not easy to remove them.

By these, and perhaps other means, opinions come to be settled and fixed in men's minds, which, whether true or false, there they remain in reputation as substantial material truths, and so are seldom questioned or examined by those who entertain them: and if they happen to be false, as in most men the greatest part must necessarily be, they put a man quite out of the way in the whole course of his studies; and though in his reading and inquiries he flatters himself that his design is to inform his understanding in the real knowledge of truth,

yet in effect it tends and reaches to nothing but the confirming of his already received opinions, the things he meets with in other men's writings and discoveries being received or neglected as they hold proportion with those anticipations which before had taken possession of his mind.

This will plainly appear if we look but on an instance or two of it. It is a principal doctrine of the Roman party to believe that their Church is infallible; this is received as the mark of a good Catholic, and implicit faith, or fear, or interest, keeps all men from questioning it. This being entertained as an undoubted principle, see what work it makes with Scripture and reason; neither of them will be heard-the speaking with never so much clearness and demonstration-when they contradict any of the doctrines or institutions; and though it is not grown to that height,

barefaced to deny the Scripture, yet interpretations and distinctions, evidently contrary to the plain sense and to the common apprehensions of men, are made use of to elude its meaning, and preserve entire the authority of this their principle, that the Church is infallible.

On the other side, make the light within our guide, and see what will become of reason and Scripture. An Hobbist, with his principle of self-preservation, whereof himself is to be judge, will not easily admit a great many plain duties of morality. The same must necessarily be found in all men who have taken up principles without examining the truth of them. It being here, then, that men take up prejudice to truth without being aware of it, and afterwards, like men of corrupted appetites,

when they think to nourish themselves, generally feed only on those things that suit with and increase the vicious humour,-this part is carefully to be looked after. These ancient preoccupations of our minds, these several and almost sacred opinions, are to be examined, if we will make way for truth, and put our minds in that freedom which belongs and is necessary to them.

A mistake is not the less so, and will never grow into a truth, because we have believed it a long time, though perhaps it be the harder to part with; and an error is not the less dangerous, nor the less contrary to truth, because it is cried up and had in veneration by any party, though it is likely we shall be the less disposed to think it so.

Here, therefore, we have need of all our force and all our sincerity; and here it is we have use of the assistance of a serious and sober friend, who may help us sedately to examine these our received and beloved opinions; for the mind by itself being prepossessed with them cannot so easily question, look round, and argue against them.

They are the darlings of our minds, and it is as hard to find fault with them, as for a man in love to dislike his mistress: there is need, therefore, of the assistance of another, at least it is very useful impartially to show us their defects, and help us to try them by the plain and evident principle of reason or religion.