The young neurologist in Hamburg did not know this history.

It is only at the end of my talk with the neurologist that I notice he wears a hearing aid. I want to ask if he knows about “100 Percent,” the film produced by deaf Germans to show they could assimilate and be productive citizens who worked. Did he know the hereditary deaf were singled out not only by the German authorities but also by those with acquired deafness who tried to save themselves? Too often, even those of us with disabilities do not know our own history.

Not many people know about disability history in the United States. They do not know that in the United States in 1927, Justice Oliver Wendell Holmes wrote that “three generations of imbeciles are enough” as part of his opinion in Buck v. Bell, in which the Supreme Court ruled that compulsory sterilization of the “unfit” was constitutional. This decision has never been expressly overturned.

Many Americans still do not know about the so-called “ugly laws,” which in many states, beginning in the late 1860s, deemed it illegal for persons who were “unsightly or unseemly” to appear in public. The last of these laws was not repealed until 1974.

Why is it important to know this history? We often say what happened in Nazi Germany couldn’t happen here. But some of it, like the mistreatment and sterilization of the disabled, did happen here.

A reading of Hoche and Binding’s “Permitting the Destruction of Unworthy Life” shows the similarity between what they said and what exponents of practical ethics, such as Peter Singer, say about the disabled today. As recently as 2015, Singer, talking with the radio host Aaron Klein on his show, said, “I don’t want my health insurance premiums to be higher so that infants who can experience zero quality of life can have expensive treatments.”

These philosophers talk about the drain on “resources” caused by lives lived with a disability, which eerily echoes what Hoche and Binding wrote about the “financial and moral burden” on “a person’s family, hospital, and state” caused by what they deem lives “unworthy of living.”

Experts point out the recent Republican health care proposals would strip Medicaid funding that helps the elderly, the poor and the disabled live healthier and more dignified lives. A recent New York Times article quoted the Rev. Susan Flanders, a retired Episcopal priest, as saying: “What we’re paying for is something that many people wouldn’t want if they had a choice. It’s hundreds of dollars each day that could go towards their grandchildren’s education or care for the people who could get well.”