This functionary, however, has been thoroughly mystified; and the remote source of his defeat lies in the supposition that the minister is a fool, because he has acquired renown as a poet. All fools are poets; this the Prefect _feels_; and he is merely guilty of a _non distributio medii_ in thence inferring that all poets are fools." "But is this really the poet?" I asked. "There are two brothers, I know; and both have attained reputation in letters. The minister, I believe, has written learnedly on the Differential Calculus. He is a mathematician, and no poet." "You are mistaken; I know him well; he is both. As poet _and_ mathematician he would reason well; as mere mathematician he could not have reasoned at all, and thus would have been at the mercy of the Prefect." "You surprise me," I said, "by these opinions, which have been contradicted by the voice of the world. You do not mean to set at naught the well-digested idea of centuries. The mathematical reason has long been regarded as _the_ reason _par excellence_." "'_Il y a à parier_,'" replied Dupin, quoting from Chamfort, "'_que toute idée publique, toute convention reçue, est une sottise, car elle a convenue au plus grande nombre_.' The mathematicians, I grant you, have done their best to promulgate the popular error to which you allude, and which is none the less an error for its promulgation as truth. With an art worthy a better cause, for example, they have insinuated the term 'analysis' into application to algebra. The French are the originators of this practical deception; but if the term is of any importance--if words derive any value from applicability--then 'analysis' conveys, in algebra, about as much as, in Latin, '_ambitus_' implies 'ambition,' '_religio_,' 'religion,' or '_homines honesti_,' 'a set of _honorable_ men.'" "You have a quarrel on hand, I see," said I, "with some of the algebraists of Paris; but proceed."