Still in Paris, in 1975 Calligaris became involved with the Freudian school of psychoanalysis and frequented case presentations led by Jacques Lacan.

His doctoral thesis, named "The passion to become a tool", was a study into bureaucratic personality, interpreting it as an attempt of an individual to handle their neurosis.

On one of these occasions a group of psychoanalysts from São Paulo approached him and proposed he come back for fifteen days once every two months so that they can run psychoanalytic sessions together.

Among the non-academic books he wrote, Conto do Amor (Companhia das Letras, 2008), or "The Tale of Love" in English, is considered to be his principal work.

The book is semi-autobiographic: Like the author, the protagonist of The Tale of Love is a psychoanalyst, sees patients in New York and had a father engaged in the Italian anti-fascist resistance.