"I can fool you because you're a human. You have a wonderful human mind that works no different from my human mind. Usually when we're fooled, the mind hasn't made a mistake. It's come to the wrong conclusion for the right reason." - Jerry Andrus

I would say that the mind came to the wrong conclusion for the reason that felt right.

He was a very smart and creative guy.

The nervous system and the emergent mind developed mechanisms to survive, and some of those generally work in nature, but fail when presented with certain types of ambiguous, or unusual, information. The waterfall illusion demonstrates this, where you stare at a waterfall for a while, and then look elsewhere. Jerry Andrus took advantage of with his spinning spiral effect, which greatly increases the effect.

Andrus Spiral Illusion

It's also here, and other places.
Counter-Rotating Spirals Illusion

His Parabox illusion takes advantage of visual ambiguity. It's another brilliant idea.

Some of his other visual illusions, notably a person standing in an impossible wood frame, were published in Scientific American years ago. He, like Martin Gardner, was known to both magicians and scientists.

His magic was also terrific.

Jerry was also an incredibly nice guy who kept his wonderful fascination and passion for magic for life.

Uck, I had no idea he had passed until I read your post. He was so nice and I loved his respect and admiration for the spectator. He created a special bond and he valued them like no other performer I have ever come across. God bless you Mr. Andrus and Rest in Peace. You will be missed.