I have never contemplated anything higher than the reformation of my own opinions, and basing them on a foundation wholly my own. And although my own satisfaction with my work has led me to present here a draft of it, I do not by any means therefore recommend to every one else to make a similar attempt. Those whom God has endowed with a larger measure of genius will entertain, perhaps, designs still more exalted; but for the many I am much afraid lest even the present undertaking be more than they can safely venture to imitate. The single design to strip one’s self of all past beliefs is one that ought not to be taken by every one. The majority of men is composed of two classes, for neither of which would this be at all a befitting resolution: in the first place, of those who with more than a due confidence in their own powers, are precipitate in their judgments and want the patience requisite for orderly and circumspect thinking; whence it happens, that if men of this class once take the liberty to doubt of their accustomed opinions, and quit the beaten highway, they will never be able to thread the byeway that would lead them by a shorter course, and will lose themselves and continue to wander for life; in the second place, of those who, possessed of sufficient sense or modesty to determine that there are others who excel them in the power of discriminating between truth and error, and by whom they may be instructed, ought rather to content themselves with the opinions of such than trust for more correct to their own Reason.
The Philosophical Works of Descartes, ed., tr. Elizabeth S. Haldane and GRT Ross (New York: Dover, 1955, orig; Meditations on First Philosophy, orig. 1647), p. 144
It is now some years since I detected how many are the false beliefs that I had from my earliest youth admitted as true, and how doubtful was everything I had since constructed on this basis, and from that time I was convinced that I must once for all seriously undertake to rid myself of all the opinions which I formerly accepted, and commence to build anew from the foundation…
I cast not praise a fugitive and cloistered virtue, unexercised and unbreathed, that never sallies out and sees her adversary, but slinks out of the race, where that immortal garland is to be run for, not without dust and heat. Assuredly we bring not innocence into the world, we bring impurity much rather; that which purifies us is trial, and trial is by what is contrary. That virtue therefore which is but a youngling in the contemplation of evil, and knows not the utmost that vice promises to her followers, and rejects it, is but a blank virtue, not a pure; her whiteness is but an excremental whiteness. Which was the reason why our sage and serious poet Spenser, whom I dare be known to think a better teacher than Scotus or Aquinas, describing true temperance under the person of Guion, brings him in with his palmer through the cave of Mammon, and the bower of earthly bliss, that he might see and know, and yet abstain. Since therefore the knowledge and survey of vice is in this world so necessary to the constituting of human virtue, and the scanning of error to the confirmation of truth, how can we more safely, and with less danger, scout into the regions of sin and falsity than by reading all manner of tractates and hearing all manner of reason? And this is the benefit which may be had of books promiscuously read.
Lords and Commons of England, consider what nation it is whereof ye are, and whereof ye are the governors: a nation not slow and dull, but of a quick, ingenious and piercing spirit, acute to invent, subtle and sinewy to discourse, not beneath the reach of any point, the highest that human capacity can soar to. Therefore the studies of Learning in her deepest sciences have been so ancient and so eminent among us, that writers of good antiquity and ablest judgment have been persuaded that even the school of Pythagoras and the Persian wisdom took beginning from the old philosophy of this island. And that wise and civil Roman, Julius Agricola, who governed once here for Csesar, preferred the natural wits of Britain before the labored studies of the French. Nor is it for nothing that the grave and frugal Transylvanian sends out yearly from as far as the mountainous borders of Russia, and beyond the Hercynian wilderness, not their youth, but their staid men, to learn our language and our theologic arts.
Philosophy has been cultivated for many centuries by the best minds that have ever lived, and nevertheless no single thing is to be found in it which is not a subject of dispute, and in consequence which is not dubious…
No more be grieved at that which thou hast done:
Roses have thorns, and silver fountains mud;
Clouds and eclipses stain both moon and sun,
And loathsome canker lives in sweetest bud.
All men make faults, and even I in this,
Authorizing thy trespass with compare,
Myself corrupting, salving thy amiss,
Excusing thy sins more than thy sins are;
For to thy sensual fault I bring in sense–
Thy adverse party is thy advocate–
And ‘gainst myself a lawful plea commence:
Such civil war is in my love and hate
That I an accessory needs must be
To that sweet thief which sourly robs from me.
There are others who, when they would cure this disease, recommend that the subject of predestination should scarcely if ever be mentioned, and tell us to shun every question concerning it as we would a rock. Although their moderation is justly commendable in thinking that such mysteries should be treated with moderation, yet because they keep too far within the proper measure, they have little influence over the human mind, which does not readily allow itself to be curbed. Therefore, in order to keep the legitimate course in this matter, we must return to the word of God, in which we are furnished with the right rule of understanding. For Scripture is the school of the Holy Spirit, in which as nothing useful and necessary to be known has been omitted, so nothing is taught but what it is of importance to know. Every thing, therefore delivered in Scripture on the subject of predestination, we must beware of keeping from the faithful, lest we seem either maliciously to deprive them of the blessing of God, or to accuse and scoff at the Spirit, as having divulged what ought on any account to be suppressed. Let us, I say, allow the Christian to unlock his mind and ears to all the words of God which are addressed to him, provided he do it with this moderation viz. that whenever the Lord shuts his sacred mouth, he also desists from inquiry. The best rule of sobriety is, not only in learning to follow wherever God leads, but also when he makes an end of teaching, to cease also from wishing to be wise.
On the Revolutions of the Heavenly Spheres (De Revolutionibus Orbium Coelestium), cited in Western Civilization: A Brief History, Jackson S. Spielvogel (Cengage Learning: 2010; original 1543), p. 344.
For a long time, then, I reflected on this confusion in the astronomical traditions concerning the derivation of the motions of the universe’s spheres. I began to be annoyed that the movements of the world machine, created for our sake by the best and most systematic Artisan of all, were not understood with greater certainty by the philosophers, who otherwise examined so precisely the most insignificant trifles of this world. For this reason I undertook the task of rereading the works of all the philosophers which I could obtain to learn whether anyone had ever proposed other motions of the universe’s spheres than those expounded by the teachers of astronomy in the schools. And in fact first I found in Cicero that Hicetas supposed the earth to move. Later I also discovered in Plutarch that certain others were of this opinion. I have decided to set his words down here, so that they may be available to everyone: “Some think that the eart remains at rest. But Philolaus the Pythagorean believes that, like the sun and moon, it revolves around the fire in an oblique circle. Heraclides of Pontus and Exphantus the Pythagorean make the earth move, not in a progressive motion, but like a wheel in a rotation from the west to east about its own center.”
Institutes of the Christian Religion, tr. Ford Lewis Battles and ed. John T. McNeill (Philadelphia: Westminster Press, 1960, orig. 1536), I, xiii, 1, p. 146.
For how can the human mind measure off the measureless essence of God according to its own little measure, a mind as yet unable to establish for certain the nature of the sun’s body, though men’s eyes daily gaze upon it? Let us then willingly leave to God the knowledge of himself … But we shall be “leaving it to him” if we conceive him to be as he reveals himself to us, without inquiring about him elsewhere than from his Word.