not no(thing

 

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It is impossible for us to know the reactions of beings constituted in a different way. It is, however, reasonable to think that in the same world ... different worlds are perceived by different beings according to the nature of their respective organs of perception.

[...] Does that mean that in absolute truth our senses have made contact with a real horse, a real apricot, etc.? There is no proof of this, for the only existing proof depends on the evidence of the senses ...

[...] We cannot presume any thing more than the existence of a stimulus which has caused the sensation that we have felt, a sensation which we have interpreted in our own way, adding to it images of our own invention.

Should we then believe that we have been taken in by a pure mirage? Not entirely. Probably the stimulus corresponds to something, but this something, that is to say the object of some kind with which one of our senses has made contact, remains unknown to us.


—Alexandra David-Néel
The Secret Oral Teachings in Tibetan Buddhist Sects

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Anyone who has common sense will remember that the bewilderments of the eyes are of two kinds, and arise from two causes, either from coming out of the light or from going into the light, which is true of the mind's eye, quite as much as of the bodily eye; and he who remembers this when he sees any one whose vision is perplexed and weak, will not be too ready to laugh; he will first ask whether that soul of man has come out of the brighter light, and is unable to see because unaccustomed to the dark, or having turned from darkness to the day is dazzled by excess of light. 

And he will count the one happy in his condition and state of being, and he will pity the other; or, if he has a mind to laugh at the soul which comes from below into the light, there will be more reason in this than in the laugh which greets him who returns from above out of the light into the den.


—Plato (c.424 - 348 BC)
Republic, The Allegory of the Cave

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