He was born in New York City to Jessie Nayer and Fields Medal-winning mathematician Jesse Douglas, and raised by relatives in Forest Hills, N.Y., after his mother died in a car accident when he was 12.

At Princeton he majored in mathematics and graduated with honors and membership in the scientific honor society Sigma XI. He took his meals at Key and Seal. Lew earned a master’s degree at the University of California, Berkeley, then taught in Monterey and East Bay prep schools. Summers involved curriculum development and gardening.

He remained active after his retirement in 2007 in Asilomar, an organization for mathematics teachers in Northern California. He also found time for organized folk dancing with the Westwind International Folk Ensemble and Jubilee American Dance Theater (winning a variety of prizes, in particular by meeting his final wife, Diana Greenleaf).

Always active in community affairs, he was deeply involved in the passage of the California DISCLOSE Act of 2017, which made political advertising much more transparent.

He is survived by his wife, Diana; and his son, Jason. We send condolences on the loss of this good and gifted man who did all he could to make the world better and make mathematics more understandable to many.