Jason Polan, an incessant sketcher whose eclectic drawings and art projects — one was called “The Every Piece of Art in the Museum of Modern Art Book” — made him one of the quirkiest and most prolific denizens of the New York art scene, died on Monday in New York. He was 37.

His family said the cause was cancer.

Mr. Polan’s signature project for the last decade or so was “Every Person in New York,” in which he set himself the admittedly impossible task of drawing everyone in New York City. He kept a robust blog of those sketches, and by the time he published a book of that title in 2015 — which he envisioned as Vol. 1 — he had drawn more than 30,000 people.

These were not sit-for-a-portrait-style drawings. They were quick sketches of people who often didn’t know they were being sketched, done on the fly, with delightfully unfinished results, as Mr. Polan wrote in the book’s introduction.