The pre-Socratic Greek philosopher <a href="https://www./author/show/357208.Parmenides" title="Parmenides" rel="nofollow">Parmenides</a> taught that the only things that are real are things which never change... and the pre-Socratic Greek philosopher <a href="https://www./author/show/77989.Heraclitus" title="Heraclitus" rel="nofollow">Heraclitus</a> taught that everything changes. If you superimpose their two views, you get this result: Nothing is real.