This play of fate through constraint and freedom becomes manifest - says Szondi - in important domains of life: choices in love, friendship, profession, disease and death. These choices are not necessarily made consciously. But every domain reveals an intention (a choice) resulting from the interactions between constraint and freedom. Szondi calls it - referring to Goethe - "Wahlverwantschafte", elective affinities or preferences.
Starting from these clinical intuitions Szondi explored family trees and relations. His specific genetic theory is not recognised by present day human geneticists. Szondi claimed to have discovered a new domain of psychodynamic life he called "the family unconscious", that he situated between Freud's individual unconscious and Jung's collective unconscious.
Looking for a simplification of the research of one's - familial - determinants, Szondi developed a test method based upon the principle of choice. In the test one is invited to express his/her sympathy and antipathy for photo's of mentally ill persons, assuming that the mentally ill person personifies in a radical way the specific factors of the human drive(s).
This is the analytical sense of Szondi's theory. The genetic approach anchors the drives in the genetic material and constitutes the biologising foundation. Szondi developed an alternative form of active analytic psychotherapy based upon his biological - dynamic theory: the Schicksalsanalytic Therapy (fate analytical therapy). This shows probably influences of the Budapest psychoanalytical. school (Ferenczi, Balint, a/o.) he belonged to.