Carl Jung: A point exists at about the thirty-fifth year when things begin to change
A point exists at about the thirty-fifth year when things begin to change, it is the first moment of the shadow side of life, of the going down to death. It is clear that Dante found this point and those who have read Zarathustra will know that Nietzsche also discovered it. When this turning point comes people meet it in several ways: some turn away from it; others plunge into it; and something important happens to yet others from the outside. If we do not see a thing Fate does it to us. ~Carl Jung, The Black Books, Vol. I, Page 11
Carl Jung Depth Psychology Blog