He writes in French rather than Latin to be judged by those using unprejudiced natural reason rather… — René Descartes

He writes in French rather than Latin to be judged by those using unprejudiced natural reason rather than by deference to the ancients; competent judges with both good sense and study will not reject arguments because they are in the vulgar tongue.

By René Descartes, from Discours de la méthode

Key Arguments

He expects readers employing unprejudiced natural reason to be better judges than those who heed the ancients only.
Those who combine good sense with scholarly habits—his desired judges—will not be so partial to Latin as to refuse to listen because of language.

Source Quotes

Though artisans may not be able at once to execute the invention which is explained in the "Dioptrics," I do not think that any one on that account is entitled to condemn it; for since address and practice are required in order so to make and adjust the machines described by me as not to overlook the smallest particular, I should not be less astonished if they succeeded on the first attempt than if a person were in one day to become an accomplished performer on the guitar, by merely having excellent sheets of music set up before him. And if I write in French, which is the language of my country, in preference to Latin, which is that of my preceptors, it is because I expect that those who make use of their unprejudiced natural reason will be better judges of my opinions than those who give heed to the writings of the ancients only; and as for those who unite good sense with habits of study, whom alone I desire for judges, they will not, I feel assured, be so partial to Latin as to refuse to listen to my reasonings merely because I expound them in the vulgar tongue. In conclusion, I am unwilling here to say anything very specific of the progress which I expect to make for the future in the sciences, or to bind myself to the public by any promise which I am not certain of being able to fulfill; but this only will I say, that I have resolved to devote what time I may still have to live to no other occupation than that of endeavoring to acquire some knowledge of Nature, which shall be of such a kind as to enable us therefrom to deduce rules in medicine of greater certainty than those at present in use; and that my inclination is so much opposed to all other pursuits, especially to such as cannot be useful to some without being hurtful to others, that if, by any circumstances, I had been constrained to engage in such, I do not believe that I should have been able to succeed.

Key Concepts

And if I write in French, which is the language of my country, in preference to Latin, which is that of my preceptors,
it is because I expect that those who make use of their unprejudiced natural reason will be better judges of my opinions than those who give heed to the writings of the ancients only;
and as for those who unite good sense with habits of study, whom alone I desire for judges, they will not, I feel assured, be so partial to Latin as to refuse to listen to my reasonings merely because I expound them in the vulgar tongue.

Context

Part 6, lines 1158–1194; linguistic and audience strategy for presenting his philosophy.