The things of this world which our senses perceive have no true being; they always become, they never are
 Arthur Schopenhauer, The World as Will and Representation (1819). copy citation

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Author Arthur Schopenhauer
Source The World as Will and Representation
Topic senses world
Date 1819
Language English
Reference
Note Translated by R. B. Haldane and J. Kemp
Weblink http://www.gutenberg.org/files/38427/38427-h/38427-h.html

Context

“This extends even to our own ego, and we know it only as phenomenon, and not according to what it may be in itself.” This is the meaning and content of the doctrine of Kant in the important respect we are considering. What Plato says is this:—“The things of this world which our senses perceive have no true being; they always become, they never are: they have only a relative being; they all exist merely in and through their relations to each other; their whole being may, therefore, quite as well be called a non-being. They are consequently not objects of a true knowledge” source