Is it true that a dangerous method is it a true story based on the following text?

A Dangerous Method is a 2011 German-Canadian historical film directed by David Cronenberg and starring Keira Knightley, Viggo Mortensen, Michael Fassbender, and Vincent Cassel. The screenplay was adapted by writer Christopher Hampton from his 2002 stage play The Talking Cure, which was based on the 1993 non-fiction book by John Kerr, A Most Dangerous Method: The story of Jung, Freud, and Sabina Spielrein.
yes