This page contains a collection of quotes on self-knowledge, arranged in roughly chronological order. These quotes are all genuine and details about the author, book, chapter number, and translation are included where applicable. Quotes that begin with a section of bold text are my personal favourites. Without further ado, here are fourteen (real) quotes by philosophers on self-knowledge:
Critias: Self-knowledge would certainly be maintained by me to be the very essence of knowledge, and in this I agree with him who dedicated the inscription, ‘Know thyself!’ at Delphi.
– Plato, Charmides, 164B, trans. Benjamin Jowett
Critias: The wise or temperate man, and he only, will know himself
– Plato, Charmides, 167A, trans. Benjamin Jowett
How much trouble he avoids who does not look to see what his neighbour says or does or thinks, but only to what he does himself, that it may be just and pure
– Marcus Aurelius, Meditations, IV, 18, trans. George Long
Look within. Within is the fountain of good, and it will ever bubble up, if thou wilt ever dig.
– Marcus Aurelius, Meditations, VII, 59, trans. George Long
I have often wondered how it is that every man loves himself more than all the rest of men, but yet sets less value on his own opinion of himself than on the opinion of others.
– Marcus Aurelius, Meditations, XII, 4, trans. George Long
Withdraw into yourself and look. And if you do not find yourself beautiful yet, act as does the creator of a statue that is to be made beautiful: he cuts away here, he smoothes there, he makes this line lighter, this other purer, until a lovely face has grown upon his work. So do you also: cut away all that is excessive, straighten all that is crooked, bring light to all that is overcast, labour to make all one glow of beauty and never cease chiselling your statue, until there shall shine out on you from it the godlike splendour of virtue, until you shall see the perfect goodness surely established in the stainless shrine.
– Plotinus, First Ennead, VI, 9, trans. MacKenna & Page
If, as we who study ourselves have learned to do, each man who hears a true statement immediately considered how it properly pertains to him, each man would find that it is not so much a good saying as a good whiplash to the ordinary stupidity of his judgement.
– Michel de Montaigne, Essays, I, 23, Of Custom, trans. Donald Frame
It is a rare life that remains well ordered even in private. Any man can play his part in the side show and represent a worthy man on the boards; but to be disciplined within, in his own bosom, where all is permissible, where all is concealed—that’s the point.
– Michel de Montaigne, Essays, III, 2, Of Repentance, trans. Donald Frame
For a long time I had remarked that it is sometimes requisite in common life to follow opinions which one knows to be most uncertain, exactly as though they were indisputable, as has been said above. But because in this case I wished to give myself entirely to the search after truth, I thought that it was necessary for me to take an apparently opposite course, and to reject as absolutely false everything as to which I could imagine the least ground of doubt, in order to see if afterwards there remained anything in my belief that was entirely certain. . . . But immediately afterwards I noticed that whilst I thus wished to think all things false, it was absolutely essential that the ‘ I ‘ who thought this should be somewhat, and remarking that this truth “I think therefore I am” was so certain and so assured that all the most extravagant suppositions brought forward by the sceptics were incapable of shaking it, I came to the conclusion that I could receive it without scruple as the first principle of the Philosophy for which I was seeking.
– René Descartes, Discourse on the Method, IV, trans. Haldane & Ross
Man is to himself the most wonderful object in nature; for he cannot conceive what the body is, still less what the mind is, and least of all how a body should be united to a mind. This is the consummation of his difficulties, and yet it is his very being.
– Blaise Pascal, Pensées, II, 72, trans. W. F. Trotter
The nature of self-love and of this human Ego is to love self only and consider self only. But what will man do? He cannot prevent this object that he loves from being full of faults and wants. He wants to be great, and he sees himself small. He wants to be happy, and he sees himself miserable. He wants to be perfect, and he sees himself full of imperfections. He wants to be the object of love and esteem among men, and he sees that his faults merit only their hatred and contempt. This embarrassment in which he finds himself produces in him the most unrighteous and criminal passion that can be imagined; for he conceives a mortal enmity against that truth which reproves him, and which convinces him of his faults. He would annihilate it, but, unable to destroy it in its essence, he destroys it as far as possible in his own knowledge and in that of others; that is to say, he devotes all his attention to hiding his faults both from others and from himself, and he cannot endure either that others should point them out to him, or that they should see them.
Truly it is an evil to be full of faults; but it is a still greater evil to be full of them, and to be unwilling to recognise them, since that is to add the further fault of a voluntary illusion.
– Blaise Pascal, Pensées, VII, 450, trans. W. F. Trotter
Why is it that, in spite of all the mirrors in the world, no one really knows what he looks like?
– Arthur Schopenhauer, Further Psychological Observations, trans. T. Bailey Saunders
Because the tyranny of opinion is such as to make eccentricity a reproach, it is desirable, in order to break through that tyranny, that people should be eccentric. Eccentricity has always abounded when and where strength of character has abounded; and the amount of eccentricity in a society has generally been proportional to the amount of genius, mental vigour, and moral courage which it contained. That so few now dare to be eccentric, marks the chief danger of the time.
– John Stuart Mill, On Liberty, III
We are unknown, we knowers, ourselves to ourselves: this has its own good reason. We have never searched for ourselves—how should it then come to pass, that we should ever find ourselves?
– Friedrich Nietzsche, The Genealogy of Morals, Preface, 1, trans. Horace B. Samuel
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