Over the past couple of days I’ve noticed so much discussion about people claiming various things about people who lived, 200, 500, 1000 years ago—namely their medical problems. I’m going to name some names....
The first claim that I came across, that I saw upset several people in fact, was the claim that Democritus had autism, or was on the autism spectrum. I saw one person argue that it would be simply far too difficult to make such a claim because their simply did not exist enough evidence to substantiate such a claim about a man living in Ancient Greece.
The next claim that I came across - that was particularly shocking to me - was that it is apparently true that Julius Caesar had epilepsy. Again, I’m not saying it’s false but I also don’t know that it is true. The next person I saw, that also apparently had epilepsy was Fyodor Dostoyevsky.
But yeah, can we really know if these historical personages had these illnesses, or is there some difficulty in some case perhaps with people like Democritus?
It is obvious that medicine has come a very long way and most of the diagnoses we have today would've been completely unknown to ancient people. In fact, our way of looking at health and disease would've been utterly incomprehensible to them. Add to that the fact that the recording of history is never perfect and something is always lost, and it becomes impossible for us to tell who suffered from what.
That said, occasionally a very brilliant doctor has recorded the signs and symptoms of the disease in such great detail that we can diagnose it today. For example, Galen's detailed description of the Antonine plague allows us to confidently recognise the disease as smallpox. Anthony can Leeuwenhoek wrote a precise description of his own disease which we know today as respiratory myoclonus. Sudor anglicus, a mysterious illness that ravaged England between 1485 and 1551, during which time it spread as far as Russia, was described by John Caius. The affliction remained a mystery until the 1990s, when it was finally found to correspond to a newly discovered viral disease, Hantavirus Pulmonary Syndrome (HPS).
The bottom line is that it is generally impossible to know about the exact nature of the illness any given pre-modern figure suffered from, but occasionally it may be possible.