The theory of evolution was fabricated by a mental patient. Darwin's mental problems were considered so severe that Picover (1998, p. 289) included Darwin in his collection of historical persons that he calls "strange brains . . . eccentric scientists, and madmen." That Darwin suffered from several severely disabling maladies is not debated; the only debate is what caused them (Pasnau, 1990, p. 121).
Colp (1977, p. 97) concluded that "much of Darwin's daily life was lived on a rack which consisted of fluctuating degrees of pain" that was sometimes so severe that Darwin called it "distressingly great." Darwin's many psychological or psychologically influenced physical health symptoms included severe depression, insomnia, hysterical crying, dying sensations, shaking, fainting spells, muscle twitches, shortness of breath, trembling, nausea, vomiting, severe anxiety, depersonalization, seeing spots, treading on air and vision, and other visual hallucinations (Barloon and Noyes, 1997, p. 139; Picover, 1998, p. 290; Colp, 1977, p. 97; Bean, 1978, p. 573). The physical symptoms included headaches, cardiac palpitations, ringing in ears (possibly tinnitus), painful flatulence, and gastric upsets—all of which commonly have a psychological origin (Pasnau, 1990). Colp noted that "behind these symptoms there was always a core of anxiety and depression" (1977, p. 97). Some speculate that part of Darwin's mental problems were due to his nagging, gnawing fear that he had devoted his "life to a fantasy"—and a "dangerous one" at that (Desmond and Moore, 1991, p. 477). This fear was that his theory was false and there was, in fact, a divine Creator.

Darwin was clearly a very troubled man and suffered from severe emotional problems for most of his adult life, especially when he was in the prime of life. The exact cause of his mental and many physical problems has been much debated and may never be known for certain. Since Darwin wrote extensively about his mental and physical problems, we have much material on which to base a reasonable conclusion about this area of his life. The diagnosis of the cause of his mental and physical problems includes a variety of debilitating conditions, but agoraphobia with the addition of psychoneurosis is most probably correct.