The soul is as familiar to us as the skin.

In 1839, Theodor Schwann published his Microscopical researches into the accordance in the structure and growth of animals and plants, the basis of cell theory.

In 1844, Søren Kierkegaard published the Concept of Anxiety: A Simple Psychologically Orienting Deliberation on the Dogmatic Issue of Hereditary Sin.

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"To be hearing the inspirations of the angel when one is kissing the flames is a condition so implicit with agony that it took eighteen centuries of Christendom before Kierkegaard could come back alive with the knowledge that such moments not only existed but were the characteristic way modern man found knowledge of his soul — which is to say that he found it by the act of perceiving that he was most certainly losing it." -Norman Mailer, preface to Deaths for the Ladies (and Other Disasters)