The act of birth is the first experience of anxiety, and thus the source and prototype of the affect of anxiety.
(Sigmund Freud (1856-1939), Austrian psychiatrist. repr. in Complete Works, vol. 5, eds. James Strachey and Anna Freud (1953). The Interpretation of Dreams, ch. 6, sct. E (1900), footnote added (1909).)
It suggested, too, that the same experience always gives birth to the same sort of belief or religion.
(Henry David Thoreau (1817-1862), U.S. philosopher, author, naturalist. "The Allegash and East Branch" (1864) in The Maine Woods (1864), in The Writings of Henry David Thoreau, vol. 3, p. 201, Houghton Mifflin (1906).)