In the past, in many societies, people with epilepsy were thought to be possessed by demons and were often burned at the stake. Other societies thought that people with epilepsy had inferior or weak minds. People with epilepsy were discriminated against, abused, and even punished for having seizures. Fear and lack of understanding help maintain old, incorrect attitudes.
http://science.jrank.org/pages/cma5hkecsy/Epilepsy-Seizures-Historical-Perspective.html
How true is that, in the past, people practiced a sort of eugenics against the mentally ill or otherwise disabled people? (We might as well include congenital physical infirmities to make it as broad as possible).
Errrr, I'm not really sure what societies they're talking about here, but it's certainly not that widespread a practice, and in fact I've never heard of such things. Now, granted, I don't know anything of the practices in the Middle Ages, which it seems that this passage is referring to, but I can definitively tell you that in antiquity this wasn't the case at all. The Greek term for epilepsy is the "Sacred Disease," the nature of which is the subject of possibly the greatest of the works of the Hippocratic Corpus, which is the first text that sets out to prove a naturalistic origin of unexplainable diseases and not a supernatural one. Now, granted, the fact that it was called the Sacred Disease doesn't necessarily mean that it was a good thing, since it was perfectly possible, although unlikely, to be possessed by malevolent spirits as well, but generally it wasn't. There was a tradition in antiquity that epileptic fits often were a sign of great genius and divine favor, and there are stories that everyone from Caesar to Alexander suffered from epilepsy or other seizures. This doesn't mean that epileptics were necessarily accepted--Hippocrates notes as a sign that the disease is of natural origins and not divine that epileptics often can tell that an attack is coming, and hide themselves from the crowd to avoid being judged or pointed to as an oddity (if it were a divine disease the onset would be sudden and without warning).
Now this article seems to conveniently want to forget, or at least neglects to mention, the fact that since the Hippocratics identified the natural cause of epilepsy (mind you, they had kind of a silly explanation for it involving a buildup of phlegm that affected the brain, but at least they understood that it was a natural disease and that it was the brain and not the soul or whatever that was being attacked) Greek medicine seems to have accepted generally the conclusion that it was a disease of the brain. Galen, for example, divides epileptic fits into three sub-categories, in all of which, he says, the brain is diseased.
Epilepsy in Babylonia to my understanding was regarded as a disease, caused in the same manner as other diseases and mental illnesses by the "hand of a ghost"(that is, an unquiet or evil spirit) or by other like forces, and treated as such where it was considered treatable. It is true that some forms of what are called "epilepsy" were regarded as incurable, but this is by no means a universal fact. Having said that, any discussion of epilepsy is bound to run into the problem of equating Babylonian medical terminology with modern diseases. The principle modern works that might be of interest are:
M. Stol, Epilepsy in Babylonia
Hector Avalos, "Epilepsy in Mesopotamia Reconsidered", in Disease in Babylonia, ed. I.L. Finkel and M.J. Geller
JoAnneScurlock and Burton Anderson, Diagnoses in Assyrian and Babylonian Medicine
Excuse me can I ask a piggy back question? When did the Catholic church stop officially exorcising people and start recognising mental illness?