Gaze steadfastly at things which, though far away, are yet present to the mind.

You must learn all things, both the unshaken heart of persuasive truth, and the opinions of mortals in which there is no true warranty.

Give me the power to produce fever and I’ll cure all disease.

Let reason alone decide.

The only roads of enquiry there are to think of: one, that it is and that it is not possible for it not to be, this is the path of persuasion (for truth is its companion); the other, that it is not and that it must not be - this I say to you is a path wholly unknowable.

Never will this prevail, that the things that are not are — bar your thought from this road of inquiry.

Every thing is of the nature of no thing.