I found a book titled “Mongoloid development” in an old trunk when I was eight. My mother had stored old guides there — research books on raising children with special needs. When my sister was born, the prevailing terms ranged from retarded to handicapped to disabled.

Refusing to place her in an institution, my mother invented a new nickname and term every week, building up my sister’s remarkable and esteemed position in our family. She was Pie: an angel, a porter, a ‘forever baby’ and effortless winner of the ‘Pie Young Award for very, very cute.’

It was never clear how I should describe my sister. I found it easier to go straight for “my sister has Down’s Syndrome” — which always seemed to clarify her state in people’s minds and settle the awkwardness. Even now, saying “intellectually disabled” feels wrong and insulting, like it would only take a smirk to turn it into a sarcastic quip on the Daily Show.

If we can define a condition, the potential ambiguity or insult seems to fade away. The valley of insults exists in the ambiguity. Cognition and brain function, measured at how we perform certain tasks we see as ‘intelligent,’ is affected by many factors beyond how we’re born.

Any given day holds the potential for errors in speech, for a tired, stressed, survival-mode brain to misfire in desperation. “What an idiot” simplifies and avoids the deeper “why” to demote someone otherwise considered to be in the realm of normal capacity.

Imagine defending someone from a standup comic picking on people in the crowd.

“Hey c’mon, he’s an idiot” would only draw further laughs.

“Not cool, move on man. He’s autistic.” is still likely to shut down the attack and embarrass the bully.