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Truth

• Few look for truth; many prowl about for a reputation of profundity by arrogantly challenging whichever arguments are the best.
• I concluded that I might take as a general rule the principle that all things which we very clearly and obviously conceive are true: only observing, however, that there is some difficulty in rightly determining the objects which we distinctly conceive.
• I did not imitate the sceptics who doubt only for doubting’s sake, and pretend to be always undecided; on the contrary, my whole intention was to arrive at a certainty, and to dig away the drift and the sand until I reached the rock or the clay beneath.
• In philosophy, when we make use of false principles, we depart the farther from the knowledge of truth and wisdom exactly in proportion to the care with which we cultivate them, and apply ourselves to the deduction of diverse consequences from them, thinking that we are philosophizing well, while we are only departing the farther from the truth; from which it must be inferred that they who have learned the least of all that has been hitherto distinguished by the name of philosophy are the most fitted for the apprehension of truth.
• In the matter of a difficult question it is more likely that the truth should have been discovered by the few than by the many.
• It is best not to go on for great quest for truth, it will only make you miserable.
• So blind is the curiosity by which mortals are possessed, that they often conduct their minds along unexplored routes, having no reason to hope for success, but merely being willing to risk the experiment of finding whether the truth they seek lies there.
• The entire method consists in the order and arrangement of the things to which the mind’s eye must turn so that we can discover some truth.
• The first precept was never to accept a thing as true until I knew it as such without a single doubt.
• There is nothing more ancient than the truth.
• There is nothing so far removed from us to be beyond our reach, or so far hidden that we cannot discover it.
• Thus, each truth discovered was a rule available in the discovery of subsequent ones.
• Truths are more likely to be discovered by one man than by a nation.
• When it is not in our power to follow what is true, we ought to follow what is most probable.
• If I go for the alternative which is false, then obviously I shall be in error; if I take the other side, then it is by… chance that I arrive at the truth, and I shall still be at fault…. In this incorrect use of free will may be found the privation which constitutes the essence of error.

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Knowledge

• Although my knowledge grows more and more, nevertheless I do not for that reason believe that it can ever be actually infinite, since it can never reach a point so high that it will be unable to attain any greater increase.
• The two operations of our understanding, intuition and deduction, on which alone we have said we must rely in the acquisition of knowledge.
• I was convinced that our beliefs are based much more on custom and example than on any certain knowledge.

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The merits of doubt

• Doubt is the origin of wisdom.
• For I found myself embarrassed with so many doubts and errors that it seemed to me that the effort to instruct myself had no effect other than the increasing discovery of my own ignorance.
• If you would be a real seeker after truth, it is necessary that at least once in your life you doubt, as far as possible, all things.
• The first precept was never to accept a thing as true until I knew it as such without a single doubt.
• The only thing that I know, is that I know nothing.
• Whatever I have up till now accepted as most true and assured I have gotten either from the senses or through the senses. But from time to time I have found that the senses deceive, and it is prudent never to trust completely those who have deceived us even once.
• Descartes, the father of modern philosophy … would never—so he assures us—have been led to construct his philosophy if he had had only one teacher, for then he would have believed what he had been told; but, finding that his professors disagreed with each other, he was forced to conclude that no existing doctrine was certain.  Bertrand Russell
• I doubt; therefore, I think; I think therefore I am.

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Wisdom

• Human wisdom remains always one and the same although applied to the most diverse objects and it is no more changed by their diversity than the sunshine is changed by the variety of objects which it illuminates.

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Common sense

• Common sense is the best distributed thing in the world, for we all think we possess a good share of it.
• Common sense is the most widely shared commodity in the world, for every man is convinced that he is well supplied with it.
• Common sense is the most fairly distributed thing in the world, for each one thinks he is so well-endowed with it that even those who are hardest to satisfy in all other matters are not in the habit of desiring more of it than they already have.
• Everybody thinks himself so well supplied with common sense that even those most difficult to please. . . never desire more of it than they already have.
• Nothing is more fairly distributed than common sense: no one thinks he needs more of it than he already has.
• Good sense is the most equitably distributed of all things because no matter how much or little a person has, everyone feels so abundantly provided with good sense that he feels no desire for more than he already possesses.

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Contemplation

• In order to improve the mind, we ought less to learn, than to contemplate.
• Just as we believe by faith that the greatest happiness of the next life consists simply in the contemplation of this divine majesty, likewise we experience that we derive the greatest joy of which we are capable in this life from the same contemplation, even though it is much less perfect.

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Reason and analysis

• Because reason is the only thing that makes us men, and distinguishes us from the beasts, I would prefer to believe that it exists, in its entirety, in each of us.
• The mind effortlessly and automatically takes in new ideas, which remain in limbo until verified or rejected by conscious, rational analysis.
• For each of us there is a set limit to our intellectual powers which we cannot pass.

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Thought

• Hence reason also demands that, since our thoughts cannot all be true because we are not wholly perfect, what truth they do possess must inevitably be found in the thoughts we have when awake, rather than in our dreams.
• Except our own thoughts, there is nothing absolutely in our power.

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Intuition

• Intuition is the undoubting conception of a pure and attentive mind, which arises from the light of reason alone, and is more certain than deduction.
• Intuitive knowledge is an illumination of the soul, whereby it beholds in the light of God those things which it pleases Him to reveal to us by a direct impression of divine clearness.

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Radical open mindedness

• At last I will devote myself sincerely and without reservation to the general demolition of my opinions.
• Now therefore, that my mind is free from all cares, and that I have obtained for myself assured leisure in peaceful solitude, I shall apply myself seriously and freely to the general destruction of all my former opinions.
• Some years ago I was struck by the large number of falsehoods that I had accepted as true in my childhood, and by the highly doubtful nature of the whole edifice that I had subsequently based on them. I realized that it was necessary, once in the course of my life, to demolish everything completely and start again right from the foundations if I wanted to establish anything at all in the sciences that was stable and likely to last.

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Morality

• Moral certainty is certainty which is sufficient to regulate our behaviour, or which measures up to the certainty we have on matters relating to the conduct of life which we never normally doubt, though we know that it is possible, absolutely speaking, that they may be false.

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Optimism

• An optimist may see a light where there is none, but why must the pessimist always run to blow it out?

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Happiness

• There is a difference between happiness, the supreme good, and the final end or goal toward which our actions ought to tend. For happiness is not the supreme good, but presupposes it, being the contentment or satisfaction of the mind which results from possessing it.

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Gratitude

• And as it is the most generous souls who have most gratitude, it is those who have most pride, and who are most base and infirm, who most allow themselves to be carried away by anger and hatred.
• And I shall always hold myself more obliged to those by whose favour I enjoy uninterrupted leisure than to any who might offer me the most honourable positions in the world.

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Problem solving

• Divide each difficulty at hand into as many pieces as possible and as could be required to better solve them.
• Each problem that I solved became a rule, which served afterwards to solve other problems.
• If I found any new truths in the sciences, I can say that they follow from, or depend on, five or six principal problems which I succeeded in solving and which I regard as so many battles where the fortunes of war were on my side.

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Passion and self-control

• The principal effect of the passions is that they incite and persuade the mind to will the events for which they prepared the body.
• The principal use of prudence, of self-control, is that it teaches us to be masters of our passions, and to so control and guide them that the evils which they cause are quite bearable, and that we even derive joy from them all.
• Conquer yourself rather than the world.
• Even those who have the weakest souls could acquire absolute mastery over all their passions if we employed sufficient ingenuity in training and guiding them.

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Suspending judgement

• If it is not in my power to arrive at the knowledge of any truth, I may at least do what is in my power, namely, suspend judgement.
• If I simply refrain from making a judgment in cases where I do not perceive the truth with sufficient clarity and distinctness, then it is clear that I am behaving correctly and avoiding error.
• This result could have been achieved either by his [God] endowing my intellect with a clear and distinct perception of everything about which I would ever deliberate, or simply by impressing the following rule so firmly upon my memory that I could never forget it: I should never judge anything that I do not clearly and distinctly understand.
• We call infinite that thing whose limits we have not perceived, and so by that word we do not signify what we understand about a thing, but rather what we do not understand.

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Freedom

• Neither divine grace nor natural knowledge ever diminishes freedom.

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Transcending error and falsehood

• What then is the source of my errors? They are owing simply to the fact that, since the will extends further than the intellect, I do not contain the will within the same boundaries; rather, I also extend it to things I do not understand. Because the will is indifferent in regard to such matters, it easily turns away from the true and the good; and in this way I am deceived and I sin.
• The greatest minds, as they are capable of the highest excellencies, are open likewise to the greatest aberrations; and those who travel very slowly may yet make far greater progress, provided they keep always to the straight road, than those who, while they run, forsake it.

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Life can seem like a kind of dream …

• But I cannot forget that, at other times I have been deceived in sleep by similar illusions; and, attentively considering those cases, I perceive so clearly that there exist no certain marks by which the state of waking can ever be distinguished from sleep, that I feel greatly astonished; and in amazement I almost persuade myself that I am now dreaming.
• For how do we know that the thoughts which occur in dreaming are false rather than those others which we experience when awake, since the former are often not less vivid and distinct than the latter?
• How can you be certain that your whole life is not a dream?
• It is possible that I am dreaming right now and that all of my perceptions are false.
• When I consider this carefully, I find not a single property which with certainty separates the waking state from the dream. How can you be certain that your whole life is not a dream?

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… and we cannot be sure that the “real” world even exists

• How do we know that anything really exists, that anything is really the way it seems to us through our senses?
• We do not describe the world we see, we see the world we can describe.
• The senses deceive from time to time, and it is prudent never to trust wholly those who have deceived us even once.
• Sensations are nothing but confused modes of thinking.

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That we are conscious is all we know for sure

• Even if I were to suppose that I was dreaming and whatever I saw or imagined was false, yet I could not deny that ideas were truly in my mind.
• The only secure knowledge is that I exist.

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Our sense of existence comes from the fact that we perceive and think

• I am thinking; therefore I exist. (…) I was a substance whose whole essence or nature is solely to think, and which does not require any place, or depend on any material thing, in order to exist. Accordingly, this ‘I’ – that is, the soul by which I am what I am – is entirely distinct from the body, and indeed is easier to know than the body, and would not fail to be whatever it is, even if the body did not exist.
• I can doubt everything, except one thing, and that is the very fact that I doubt. Simply put – I think, therefore I am.  Discartes
• I know that I exist; the question is, What is this ‘I’ that ‘I’ know.

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The mind and body are distinct and separate

• There is a great difference between mind and body insomuch as body is by nature always divisible, and the mind is entirely indivisible.
• On the one hand, I have a clear and distinct idea of myself, in so far as I am simply a thinking, non-extended thing [that is, a mind], and on the other hand I have a distinct idea of body, in so far as this is simply an extended, non-thinking thing. And accordingly, it is certain that I am really distinct from my body, and can exist without it.
• There is a great difference between the mind and the body, inasmuch as the body is by its very nature always divisible, while the mind is utterly indivisible. For when I consider the mind, or myself in so far as I am merely a thinking thing, I am unable to distinguish any parts within myself; I understand myself to be something quite single and complete… by contrast, there is no corporeal or extended thing that I can think of which in my thought I cannot easily divide into parts; and this very fact makes me understand that it is divisible. This one argument would be enough to show me that the mind is completely different from the body.
• It is certain that I am really distinct from my body, and can exist without it.

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The mystery of existence

• I suppose therefore that all things I see are illusions; I believe that nothing has ever existed of everything my lying memory tells me. I think I have no senses. I believe that body, shape, extension, motion, location are functions. What is there then that can be taken as true? Perhaps only this one thing, that nothing at all is certain.
• I suppose therefore that all things I see are illusions; I believe that nothing has ever existed of everything my lying memory tells me. I think I have no senses. I believe that body, shape, extension, motion, location are functions. What is there then that can be taken as true? Perhaps only this one thing, that nothing at all is certain. 

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God

• Be that as it may, there is fixed in my mind a certain opinion of long standing, namely that there exists a God who is able to do anything and by whom I, such as I am, have been created. How do I know that he did not bring it about that there is no earth at all, no heavens, no extended thing, no shape, no size, no place, and yet bringing it about that all these things appear to me to exist precisely as they do now?
• I have concluded the evident existence of God, and that my existence depends entirely on God in all the moments of my life, that I do not think that the human spirit may know anything with greater evidence and certitude.
• Instead I ought to be grateful to Him who never owed me anything for having been so generous to me, rather than think that He deprived me of those things or has taken away from me whatever He did not give me.
• Before examining this more carefully and investigating its consequences, I want to dwell for a moment in the contemplation of God, to ponder His attributes in me, to see, admire, and adore the beauty of His boundless light, insofar as my clouded insight allows. Believing that the supreme happiness of the other life consists wholly of the contemplation of divine greatness, I now find that through less perfect contemplation of the same sort I can gain the greatest joy available in this life.
• By ‘God’, I understand, a substance which is infinite, independent, supremely intelligent, supremely powerful, and which created both myself and everything else that exists. All these attributes are such that, the more carefully I concentrate on them, the less possible it seems that they could have originated from me alone. So, from what has been said it must be concluded that God necessarily exists.

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God beyond concept

• In God there is an infinitude of things which I cannot comprehend, nor possibly even reach in any way by thought; for it is the nature of the infinite that my nature, which is finite and limited, should not comprehend it.
• We call infinite that thing whose limits we have not perceived, and so by that word we do not signify what we understand about a thing, but rather what we do not understand.

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Making decisions and choices

• Situations in life often permit no delay; and when we cannot determine the course which is certainly best, we must follow the one which is probably the best. This frame of mind freed me also from the repentance and remorse commonly felt by those vacillating individuals who are always seeking as worthwhile things which they later judge to be bad.

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Reading

• The reading of all good books is indeed like a conversation with the noblest men of past centuries who were the authors of them, nay a carefully studied conversation, in which they reveal to us none but the best of their thoughts.
• The reading of all good books is like a conversation with the finest minds of past centuries.
• Bad books engender bad habits, but bad habits engender good books.

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Science and philosophy

• Science is practical philosophy.

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Mathematics

• As I considered the matter carefully it gradually came to light that all those matters only were referred to mathematics in which order and measurements are investigated, and that it makes no difference whether it be in numbers, figures, stars, sounds or any other object that the question of measurement arises. I saw consequently that there must be some general science to explain that element as a whole which gives rise to problems about order and measurement, restricted as these are to no special subject matter. This, I perceived was called ‘universal mathematics’.
• But in my opinion, all things in nature occur mathematically.
• I accept no principles of physics which are not also accepted in mathematics.
• If we possessed a thorough knowledge of all the parts of the seed of any animal (e.g. man), we could from that alone, by reasons entirely mathematical and certain, deduce the whole conformation and figure of each of its members, and, conversely if we knew several peculiarities of this conformation, we would from those deduce the nature of its seed.
• Mathematics is a more powerful instrument of knowledge than any other that has been bequeathed to us by human agency.

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Law

• A state is better governed which has few laws, and those laws strictly observed.

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Music

• The object of music is a sound. The end; to delight, and move various affections in us.

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Motion

• Give me extension and motion and I will construct the universe.
• God alone is the author of all the motions in the world.

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Mind

• For to be possessed of a vigorous mind is not enough; the prime requisite is rightly to apply it.
• I am indeed amazed when I consider how weak my mind is and how prone to error.
• It is not enough to have a good mind; the main thing is to use it well.

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Thinking and being

• The philosopher Descartes believed he had found the most fundamental truth when he made his famous statement: “I think, therefore I am.” He had, in fact, given expression to the most basic error: to equate thinking with Being and identity with thinking. The compulsive thinker, which means almost everyone, lives in a state of apparent separateness, in an insanely complex world of continuous problems and conflict, a world that reflects the ever-increasing fragmentation of the mind.  Eckhart Tolle

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Vice

• And as it is the most generous souls who have most gratitude, it is those who have most pride, and who are most base and infirm, who most allow themselves to be carried away by anger and hatred.

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• … regard this body as a machine which, having been made by the hand of God, is incomparably better ordered than any machine that can be devised by man, and contains in itself movements more wonderful than those in any machine. … it is for all practical purposes impossible for a machine to have enough organs to make it act in all the contingencies of life in the way in which our reason makes us act.
• It cannot be denied that he has had many exceptional ideas, and that he is a highly intelligent man. For my part, however, I have always been taught to take a broad overview of things, in order to be able to deduce from them general rules, which might be applicable elsewhere.
• A person has two passions for love and abhorrence. A big disposition to excessiveness has just a love, because it is more ardent and stronger.
• Archimedes, that he might transport the entire globe … demanded only a point that was firm and immovable; so also, I shall be entitled to entertain the highest expectations, if I am fortunate enough to discover only one thing that is certain and indubitable.
• But possibly I am something more than I suppose myself to be.
• Every man is indeed bound to do what he can to promote the good of others, and a man who is of no use to anyone is strictly worthless.
• I am thing that thinks: that is, a things that doubts, affirms, denies, understands a few things, is ignorant of many things, is willing, is unwilling, and also which imagines and has sensory perceptions.
• I desire to live in peace and to continue the life I have begun under the motto ‘to live well you must live unseen.’
• I experienced in myself a certain capacity for judging which I have doubtless received from God, like all the other things that I possess; and as He could not desire to deceive me, it is clear that He has not given me a faculty that will lead me to err if I use it aright.
• I hope that posterity will judge me kindly, not only as to the things which I have explained, but also to those which I have intentionally omitted so as to leave to others the pleasure of discovery.
• I should consider that I know nothing about physics if I were able to explain only how things might be, and were unable to demonstrate that they could not be otherwise.
• It is contrary to reasoning to say that there is a vacuum or space in which there is absolutely nothing.
• It is to the body alone that we should attribute everything that can be observed in us to oppose our reason.
• Let whoever can do so deceive me, he will never bring it about that I am nothing, so long as I continue to think I am something.
• My third maxim was to try always to conquer myself rather than fortune, and to change my desires rather than the order of the world, and generally to accustom myself to believing that there is nothing entirely in our power except our thoughts, so that after we have done our best regarding things external to us, everything in which we do not succeed is for us absolutely impossible.
• Nothing comes out of nothing.
• So far, I have been a spectator in this theatre which is the world, but I am now about to mount the stage, and I come forward masked.
• The chief cause of human errors is to be found in the prejudices picked up in childhood.
• To live without philosophizing is in truth the same as keeping the eyes closed without attempting to open them.
• We never understand a thing so well, and make it our own, as when we have discovered it for ourselves.
• Whenever anyone has offended me, I try to raise my soul so high that the offense cannot reach it.
• You just keep pushing. You just keep pushing. I made every mistake that could be made. But I just kept pushing.
• It is easy to hate and it is difficult to love. This is how the whole scheme of things works. All good things are difficult to achieve; and bad things are very easy to get.

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• There is nothing so strange and so unbelievable that it has not been said by one philosopher or another.
• An optimist may see a light where there is none, but why must the pessimist always run to blow it out? 
• I am accustomed to sleep and in my dreams to imagine the same things that lunatics imagine when awake.
• I’m the Descartes of anxiety; I panic therefore I am.   Richard Lewis

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