How does Tammet use numbers to understand other people’s emotions?

Tammet has synesthesia which is a rare phenomenon in humans.This phenomenon involves the perception of numbers as colors, textures and sounds. He views numbers in a 3 dimensional form and this makes it hard for Tammet to understand emotions ordinarily. Absence of numbers makes him emotionless while the presence of numbers however helps in the interpretation and understanding of how other people feel as a result of the synesthesia.

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