Date: 1764

"But behold, this soul of thought frequently has the ascendancy over the animal soul. The thinking soul orders its hands to grasp, and they grasp. It does not tell its heart to beat, its blood to run, its chyle to form; all these things happen without it: so here we have two perplexed souls which...

— Arouet, François-Marie [known as Voltaire] (1694-1778)

Date: 1764

"Nobody knows what really is the being called 'spirit', to which even you give the material name of 'spirit', which means wind."

— Arouet, François-Marie [known as Voltaire] (1694-1778)

Date: 1772

"It will remind me of what I used to be, and Pride will have to come to a standstill at the threshold of my heart."

— Diderot, Denis (1713-1784)

Date: 1777

"The minds of the negroes are contracted; because slavery destroys all the springs of the soul."

— Raynal, Guillaume Thomas (1713-1796)

Date: 1780-85; in French, 36 vols. 1749-1788

"Is it difficult to perceive that our ideas originate from our senses alone; that the objects we regard as real existences, are those concerning which the senses uniformly give the same testimony."

— Buffon, Georges Louis Leclerc, comte de (1707-1788)