A headline about paramedics being charged with killing someone got me looking at the history of "agitated delirium" and revisiting Thomas Szasz's "The Myth of Mental Illness".
I think Szasz doesn't present a good example of a non mental illness, though he does discuss "problems in living". That is, he's assuming that all physical illnesses conform to Koch's postulates or something (x germ = y disorder; or w lesion = z dysfunction).
Phillips J, Frances A, Cerullo MA, Chardavoyne J, Decker HS, First MB, Ghaemi N, Greenberg G, Hinderliter AC, Kinghorn WA, LoBello SG, Martin EB, Mishara AL, Paris J, Pierre JM, Pies RW, Pincus HA, Porter D, Pouncey C, Schwartz MA, Szasz T, Wakefield JC, Waterman GS, Whooley O, Zachar P. The six most essential questions in psychiatric diagnosis: a pluralogue part 3: issues of utility and alternative approaches in psychiatric diagnosis. Philos Ethics Humanit Med. 2012 May 23;7:9. doi: 10.1186/1747-5341-7-9. PMID: 22621419; PMCID: PMC3403926.
