[3] He was the founding senior partner and chief psychologist of a mental health corporation[4] in Ontario, Canada before he retired from clinical practice.
[11] He argues that the mind is ontologically constituted through unconscious genesis, and that subjectivity is conditioned a priori by unconscious agency, which is responsible for all forms of mental life to transpire,[22] including higher modes of consciousness, contrary to contemporary views in the philosophy of mind that place causal primacy on consciousness.
[10] He makes the controversial claim that unconscious semiotics condition and underlie the structure and function of language, subjectivity, and social dynamics.
[25][26] Mills also offered the first sustained philosophical critique of contemporary psychoanalysis in his book, Conundrums, which examines and scrutinizes relational, intersubjective, and postmodern perspectives in the field.
[32] The conference proceedings were published in the journal, Psychoanalytic Perspectives,[33] which later appeared in his book, Debating Relational Psychoanalysis: Jon Mills and his Critics.