Roger Bacon: Experience

“Reasoning draws a conclusion and makes us grant the conclusion, but does not make the conclusion certain, nor does it remove doubt so that the mind may rest on the intuition of truth, unless the mind discovers it by the path of experience.”

Roger Bacon book Opus Majus

Opus Majus, c. 1267
Source: Robert Belle Burke (2002) The Opus Majus of Roger Bacon Part 2. p. 583

Truth , Drawing

“The strongest argument proves nothing so long as the conclusions are not verified by experience.”
[H]aec vocatur scientia experimentalis, quae negligit argumenta, quoniam non certificant, quantumcunque sint fortia, nisi simul adsit experientia conclusionis. Et ideo haec docet experiri conclusiones nobiles omnium scientiarum, quae in aliis scientiis aut probantur per argumenta, aut investigantur per experientias naturales et imperfectas...

Roger Bacon book Opus Tertium

OQHI, 43 http://www.mlat.uzh.ch/MLS/text.php?tabelle=Rogerus_Baco_cps4&rumpfid=Rogerus_Baco_cps4,%20Opus%20tertium,%20%2013&level=3&corpus=4&lang=0&current_title=Opus%20tertium&links=&inframe=1&hide_apparatus= as cited in: James J. Walsch (1911) """"Science at the Medieval Universities"""" in: Popular Science, May 1911, p. 449 http://en.wikisource.org/wiki/Page:Popular_Science_Monthly_Volume_78.djvu/459
Opus Tertium, c. 1267
Context: The strongest argument proves nothing so long as the conclusions are not verified by experience. Experimental science is the queen of sciences, and the goal of all speculation.

“I shall draw… a figure (which all these matters are made clear as far as possible on a surface, but the full demonstration would require a body like the eye… The eye of a cow, pig, and other animals can be used for illustration, if anyone wishes to experiment.”

Roger Bacon book Opus Majus

v. i. iii. 3, ed. Bridges as quoted in A.C. Crombie, Robert Grossetest and the Origins of Experimental Science 1100-1700 (1953)
Opus Majus, c. 1267

Animals , Drawing

“And this [experimental] science verifies all natural and man-made things in particular, and in their appropriate discipline, by the experimental perfection, not by arguments of the still purely speculative sciences, nor through the weak, and imperfect experiences of practical knowledge. And therefore, this is the matron of all preceding sciences, and the final end of all speculation.”
Et hæc scientia certificat omnia naturalia et artificialia in particulari et in propria disciplina, per experientiam perfectam; non per argumenta, ut scientiæ pure speculativae, nec per debiles et imperfecta experientias ut scientiae operativæ. Et ideo hæc est domina omnium scientiarum præcedentium, et finis totius speculationis.

Roger Bacon book Opus Tertium

Ch 13 ed. J. S. Brewer Opera quadam hactenus inedita (1859) p. 46
Opus Tertium, c. 1267

Nature , Knowledge , Science , Perfection

“Argument is conclusive… but… it does not remove doubt, so that the mind may never rest in the sure knowledge of the truth, unless it finds it by the method of experiment. For if any man who never saw fire proved by satisfactory arguments that fire burns, his hearer's mind would never be satisfied, nor would he avoid the fire until he put his hand in it that he might learn by experiment what argument taught.”

Roger Bacon

Cited in: Carol A. Dingle (2000) Memorable Quotations: Philosophers of Western Civilization. p. 21

Truth , Knowledge , Learning

“One man I know, and one only, who can be praised for his achievements in this science. Of discourses and battles of words he takes no heed: he follows the works of wisdom, and in these finds rest. What others strive to see dimly and blindly, like bats in twilight, he gazes at in the full light of day, because he is a master of experiment. Through experiment he gains knowledge of natural things, medical, chemical, indeed of everything in the heavens or earth. He is ashamed that things should be known to laymen, old women, soldiers, ploughmen, of which he is ignorant. Therefore he has looked closely into the doings of those who work in metals and minerals of all kinds; he knows everything relating to the art of war, the making of weapons, and the chase; he has looked closely into agriculture, mensuration, and farming work; he has even taken note of the remedies, lot casting, and charms used by old women and by wizards and magicians, and of the deceptions and devices of conjurors, so that nothing which deserves inquiry should escape him, and that he may be able to expose the falsehoods of magicians. If philosophy is to be carried to its perfection and is to be handled with utility and certainty, his aid is indispensable. As for reward, he neither receives nor seeks it. If he frequented kings and princes, he would easily find those who would bestow on him honours and wealth. Or, if in Paris he would display the results of his researches, the whole world would follow him. But since either of these courses would hinder him from pursuing the great experiments in which he delights, he puts honour and wealth aside, knowing well that his wisdom would secure him wealth whenever he chose. For the last three years he has been working at the production of a mirror that shall produce combustion at a fixed distance; a problem which the Latins have neither solved nor attempted, though books have been written upon the subject.”

Roger Bacon book Opus Tertium

Bridges assumes that Bacon refers here to Peter Peregrinus of Maricourt.
Source: Opus Tertium, c. 1267, Ch. 13 as quoted in J. H. Bridges, The 'Opus Majus' of Roger Bacon (1900) Vol.1 http://books.google.com/books?id=6F0XAQAAMAAJ Preface p.xxv

Wisdom , Women , War , Books

“And because this Experimental Science is wholly ignored by the general run of students, for that reason I can not convince people of its utility unless I show at the same time its excellence and its property. This science alone, then, knows how to test perfectly by experience what can be done by nature, what by the industry of art, what by imposture; what the incantations, conjurations, invocations, deprecations, sacrifices (which are magical devices) seek and dream of; and what is done in them, so that all falsity may be removed and that only the truth of art and nature be retained. This science alone teaches one to consider all the insanities of magicians, not that they may be confirmed but that they may be avoided, just as logic considers sophistical argument.”

Roger Bacon book Opus Majus

6th part Experimental Science, Ch.2 Tr. Richard McKeon, Selections from Medieval Philosophers Vol.2 Roger Bacon to William of Ockham
Opus Majus, c. 1267

People , Truth , Dreams , Art