do. For without examining whether he has effectively succeeded in his pretension, I assume that he has done so, and it is on this supposition that I say that this expression is as different in his writings from the same saying in others who have said it by chance, as is a man full of life and strength from a corpse.
One man will say a thing of himself without comprehending its excellence, in which another will discern a marvellous series of conclusions, which make us affirm boldly that it is no longer the same expression, and that he is no more indebted for it to the one from whom he has learned it, than a beautiful tree belongs to the one who cast the seed, without thinking of it, or knowing it, into the fruitful soil which caused its growth by its own fertility.
The same thoughts sometimes put forth quite differently in the mind of another than in that of their author: unfruitful in their natural soil, abundant when transplanted. But it much oftener happens that a good mind itself makes its own thoughts produce all the fruit of which they are capable, and that afterwards others, having heard them admired, borrow them, and adorn themselves with them, but without knowing their excellence; and it is then that the difference of the same word in different mouths is the most apparent.
It is in this manner that logic has borrowed, perhaps, the rules of geometry, without comprehending their force; and thus, in placing them by chance among those that belong to it, it does not thence follow that they[1] have entered into the spirit of geometry, and I should be greatly averse if they gave no other evidence of it than that of having mentioned it by chance, to placing them on a level with that science that teaches the true method of directing the reason.
But I should be, on the contrary, strongly disposed to exclude them from it, and almost irrevocably. For to have said it by chance, without having taken care that every thing was included within it, and instead of following this light to wander blindly in useless researches, pursuing what they promise but never can give, is truly showing that they are not very clear-sighted, and much more than if they had failed to follow the light, because they had not perceived it.
