" The evil, the guilt, the profound unease of conscience, the dark foreboding, are there before our eyes, if only we would see. Man has done these things; I am a man, who has his share of human nature; therefore I am guilty with the rest and bear unaltered and indelibly within me the capacity and the inclination to do them again at any time. Even if, juristically speaking, we were not accessories to the crime, we are always, thanks to our human nature, potential criminals. In reality we merely lacked a suitable opportunity to be drawn into the infernal mêlée. None of us stands outside humanity’s black collective shadow. Whether the crime occurred many generations back or happens today, it remains the symptom of a disposition that is always and everywhere present—and one would therefore do well to possess some “imagination for evil,” for only the fool can permanently disregard the conditions of his own nature. In fact, this negligence is the best means of making him an instrument of evil. "

― C.G. Jung , The Undiscovered Self/Symbols and the Interpretation of Dreams