More than 30 years ago, the pioneering urbanist William Whyte was charged by the city of New York with the task of unraveling the mysteries of public space. Why do some such spaces attract crowds of happy visitors whilst others sit barren and empty?

Whyte's research programme, conducted with stopwatches, time-lapse videography, and lots of simple paper charts, was a spectacular success. Based on his findings, he made a series of simple and easily implemented recommendations that the city soon codified into its municipal construction codes.

William Whyte on 5th Avenue, New York, in 1989. Whyte is considered the godfather of urban psychology. Photograph: William Foley/Time & Life Pictures/Getty

Today, any visitor to New York might find any number of things to complain about but the wide availability and attractive human affordances of the city's many public spaces is not likely to be among them. Whyte's epiphany was that the way to answer important questions about how to build a commodious and psychologically healthy city lay in careful observation, collection of data and the creative ability to lay aside preconceptions and view a streetscape with a "beginner mind".

Whyte's book The Social Life of Small Urban Spaces, and the short film based on this work, are as fresh and insightful now as the day that they appeared, and are required reading and viewing for any student of urban behaviour.

Fast forward a few decades, and many things have changed, but the fundamentals remain the same. If we want to know how to make a better city, the place to start is at ground level, using observation and measurement, and applying what is known of the human sciences to those measurements to build a psychologically grounded view of the relationship between the physical design of a city and what happens there.