Table 2. Categorization of the diagnoses for Darwin’s Illness, arranged for discussion.

Diagnoses for Darwin’s illness grouped according to category. For completeness, some diagnoses appear in more than one category but are only discussed once in the text.

Category	Proposed diagnosis
Diagnoses made by Darwin and by his doctors, colleagues, and contemporaries	Nervous dyspepsia, aggravated dyspepsia, suppressed gout, malingering (“shamming”), waterbrash, sequel
Conditions supposedly acquired during his voyage with the HMS Beagle	Sequel to seasickness, voyage with the HMS Beagle, a sequel to prolonged illness Valparaiso, brucellosis, Chagas’ disease, malaria
Psychogenic, psychological diagnoses	Neurasthenia, anxiety neurosis, psychoneurosis, depressive psychosis; psychogenic – repressed hostility toward father, latent homosexuality, abhorrence to slavery; unresolved grief for mother’s death, father-son bonding; panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder; Asperger’s syndrome
Intestinal disease and disorders	Diaphragmatic hernia, lactose intolerance (“systemic”), Crohn’s disease, cyclic vomiting (CVS), Helicobacter infection, irritable bowel syndrome (IBS)
Infections	Pyorrhea, brucellosis, Chagas’ disease, malaria, Helicobacter infection, chronic borreliosis (Lyme disease)
Diagnoses, alternative medicine	Pyroluria, Candida overload
Miscellaneous	Refractive error, arsenic poisoning, porphyria, lupus erythematosus
Correct, but incomplete diagnoses	Supraventricular tachycardia, chronic fatigue, adrenal insufficiency, panic disorder, Ménière’s disease, atopic dermatitis, cyclic vomiting (CVS), Helicobacter infection
Preferred diagnosis	Maternally inherited adult-onset pathological mtDNA mutation, MELAS type