There are more things in heaven and earth, Horatio,
Than are dreamt of in your philosophy.
William Shakespeare, Hamlet Prince of Denmark
Philosophy, and in particular metaphysics, has been killed off again and again, day after day, the deed done by a variety of assassins: eighteenth-century empiricists, Hegel, Marx, positivists of every hue, Wittgenstein, and so on. But behold, after all these massacres the poor thing rises from the grave, oblivious to the fact that it is supposed to be dead, and starts walking. Where it is going it admittedly does not know, and nor does anyone else, but that is a different question.
Leszek Koakowski (1927-2009), "Our Merry Apocalypse," Is God Happy? Selected Essays, Basic Books, 2013, p.318
This reality, then, that gives their truth of the objects of knowledge and the power of knowing to the knower, you must say is the idea of the good, and you must conceive it as being the cause of knowledge  and of truth  in so far as known.
Plato, Republic, 508e, Republic II [translated by Paul Shorey, Loeb Classical Library, Harvard University Press, 1930, 1969, pp.102-105, color added]
Die Welt ist meine Vorstellung.
The world is my representation.
Arthur Schopenhauer, Die Welt als Wille und Vorstellung, Band 1, §1 [Reclam, 1987, p.3], The World as Will and Representation, Volume I [Dover Publications, 1966, E.F.J. Payne translation, p.3]