Max Planck

"The quantum theory is a theory of the elementary quanta of the cosmos and the chaos, the light and the darkness, the good and the evil, the life and the death, the beginning and the end, the alpha and the omega, the past, the present, and the future, the here and the now, the everywhere and the always, the visible and the invisible, the known and the unknown, the finite and the infinite, the possible and the impossible, the necessary and the contingent, the universal and the particular, the general and the specific, the abstract and the concrete, the simple and the complex, the whole and the part, the one and the many, the same and the different, the identity and the difference, the unity and the multiplicity, the order and the chaos, the harmony and the discord, all things and nothing, being and non-being, existence and non-existence, reality and unreality, truth and falsehood, knowledge and ignorance, wisdom and folly, beauty and ugliness, good and evil, morality and immorality, ethics and unethics, religion and irreligion, spirituality and materialism, God and atheism, the universe and the void."

— from The Origin and Development of the Quantum Theory, 1920

"The quantum theory is a theory of the elementary quanta of the cosmos and the chaos, the light and the darkness, the good and the evil, the life and the death, the beginning and the end, the alpha and the omega, the past, the present, and the future, the here and the now, the everywhere and the always, the visible and the invisible, the known and the unknown, the finite and the infinite, the possible and the impossible, the necessary and the contingent, the universal and the particular, the general and the specific, the abstract and the concrete, the simple and the complex, the whole and the part, the one and the many, the same and the different, the identity and the difference, the unity and the multiplicity, the order and the chaos, the harmony and the discord."

— from The Origin and Development of the Quantum Theory, 1920

"My original decision to devote myself to science was a direct result of the discovery which has never ceased to fill me with enthusiasm since my early youth - the comprehension of the far from obvious fact that the laws of human reasoning coincide with the laws governing the sequences of the impressions we receive from the world about us; that, therefore, pure reasoning can enable man to gain an insight into the mechanism of the latter. In that sense, it is obvious that science cannot be neutral, and cannot be isolated from life."

— from Scientific Autobiography, 1949