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• I consider as lovers of books not those who keep their books hidden in their store-chests and never handle them, but those who, by nightly as well as daily use thumb them, batter them, wear them out, who fill out all the margins with annotations of many kinds, and who prefer the marks of a fault they have erased to a neat copy full of faults.
  • Letter to an unidentified friend (1489), as translated in Collected Works of Erasmus (1974), p. 114

• A constant element of enjoyment must be mingled with our studies, so that we think of learning as a game rather than a form of drudgery, for no activity can be continued for long if it does not to some extent afford pleasure to the participant.
  • Letter to Christian Northoff (1497), as translated in Collected Works of Erasmus (1974), p. 114

• You must acquire the best knowledge first, and without delay; it is the height of madness to learn what you will later have to unlearn.
  • Letter to Christian Northoff (1497), as translated in Collected Works of Erasmus (1974), p. 114

• Do not be guilty of possessing a library of learned books while lacking learning yourself.
  • Letter to Christian Northoff (1497), as translated in Collected Works of Erasmus (1974), p. 115

• Ad Graecas literas totum animum applicui; statimque, ut pecuniam acceptero, Graecus primum autores, deinde vestes emam.
  • I have turned my entire attention to Greek. The first thing I shall do, as soon as the money arrives, is to buy some Greek authors; after that, I shall buy clothes.
  • Letter to Jacob Batt (12 April 1500); Collected Works of Erasmus Vol 1 (1974)
  • Variant translation: When I get a little money I buy books; and if any is left I buy food and clothes.

• In regione caecorum rex est luscus.
  • In the country of the blind, the one-eyed man is king.
  • Adagia (first published 1500, with numerous expanded editions through 1536), III, IV, 96
  • Also in the same passage of the Adagia is a variant: Inter caecos regnat strabus (Among the blind, the squinter rules).

• The most disadvantageous peace is better than the most just war.
  • Adagia (1508)

• For what is life but a play in which everyone acts a part until the curtain comes down?
  • The Praise of Folly (1511)

• This type of man who is devoted to the study of wisdom is always most unlucky in everything, and particularly when it comes to procreating children; I imagine this is because Nature wants to ensure that the evils of wisdom shall not spread further throughout mankind.
  • The Praise of Folly (1511)

• I have no patience with those who say that sexual excitement is shameful and that venereal stimuli have their origin not in nature, but in sin. Nothing is so far from the truth. As if marriage, whose function cannot be fulfilled without these incitements, did not rise above blame. In other living creatures, where do these incitements come from? From nature or from sin? From nature, of course. It must borne in mind that in the apetites of the body there is very little difference between man and other living creatures. Finally, we defile by our imagination what of its own nature is fair and holy. If we were willing to evaluate things not according to the opinion of the crowd, but according to nature itself, how is it less repulsive to eat, chew, digest, evacuate, and sleep after the fashion of dumb animals, than to enjoy lawful and permitted carnal relations?
  • In Praise of Marriage (1519), in Erasmus on Women (1996) Erika Rummel

• I am a lover of liberty. I will not and I cannot serve a party.
  • Spongia adversus aspergines Hutteni (1523), § 176, As quoted in Desiderius Erasmus of Rotterdam (1900) by Ephraim Emerton, p. 377
  • Variant: I am a lover of liberty. I cannot and will not serve parties.

• There is no doubt about Martin Luther's marriage, but the rumour about his wife's early confinement is false; she is said however to be pregnant now. If there is truth in the popular legend, that Antichrist will be born from a monk and a nun (which is the story these people keep putting about), how many thousands of Antichrists the world must have already!
  • Responding to rumours prompted by the marriage of Martin Luther, in a letter to François Dubois (13 March 1526), as translated in The Correspondence of Erasmus : Letters 1658 to 1801, January 1526-March 1527 (1974) edited by Charles Garfield Nauert and Alexander Dalzell, p. 79
  • Paraphrased variant: They say that the Antichrist will be born of a monk and a nun. If so, there must already be thousands of Antichrists.

• Wherever you encounter truth, look upon it as Christianity.
  • As quoted in Erasmus of Rotterdam‎ (1934) by Stefan Zweig, Eden Paul, and Cedar Paul, p. 91; also in Erasmus — The Right to Heresy (2008) by Staffan Z. Weig, p. 62

• There is nothing I congratulate myself on more heartily than on never having joined a sect.
  • As quoted in Thomas More and Erasmus (1965) by Ernest Edwin Reynolds, p. 248

• I am a citizen of the world, known to all and to all a stranger.
  • As quoted in Erasmus (1970) by György Faludy, p. 197

Unsourced

• Believe that you have it, and you have it!

• Education is of far greater importance than heredity in forming character.

• It is the friendship of books that has made me perfectly happy.

• The rules of grammar are crabbed things to many persons... it is important early to instil a taste for the best things into the minds of children, and I cannot see that anything is learned with greater success than what is learned by playing, and this is, in truth, a very harmless kind of fraud, to trick a person into his own profit.

• To know nothing is the happiest life

• Fortune favors the audacious.

Misattributed

• Dulce bellum inexpertis.
  • War is sweet to them that know it not.
    • Though Erasmus quoted this proverb in Latin at the start of his essay Bellum [War], and it is sometimes attributed to him, it originates with the Greek poet Pindar.
  • Variant translations:
  • War is sweet to those not acquainted with it
  • War is Sweet to Those Who Do Not Know It
  • War is sweet to those That never have experienced it.
  • War is delightful to those who have had no experience of it.