The problem of concept formation in psychiatric (psychopathological) thought is defined as an instante of the general epistemological problem of the criterion and set forth with reference to the discontinuities of the meta-standpoints, that underlie different modes of concept formation, such as become manifest in the work of Freud, Binswanger, Jaspers and Laing. It is argued, that these discontinuities contradict the assumption of a basic rationality in the procedures of conceptual change as implied by S. Toulmin's evolutionary theory of conceptual change and support a plea for sceptical suspension of judgement concerning the issue of the ultimate rationality or irrationality of conceptual change in scientific, c.q. psychiatric (psychopathological) thought. The last documented phase in the thought of R. D. Laing ('transcendental naturalism') is chosen for critical examination and it is argued, that, consequently held, this position leads into a 'double-bind' situation: it's (implicit) claim of being fundamental for psychiatric thought (c.q. concept formation) can only be upheld by it's ceasing to be of relevante for current psychiatrical research, and by betoming instead philosophical anthropology, aiming at making explicit the 'schizoid' structure of man's being-in-the-world. On the other side, this position can only maintain it's pretention of being relevant for current psychiatrical research, at the cost of giving up the claim of being, in any sense of the term, 'fundamental' for psychiatric thought. The present malaise in psychiatric circles, and the preoccupation of psychiatrists with problems of concept formation, is viewed as stemming from a discontent with anti-empiristic consequences of the implicit absolutist claims of the british 'anti-psychiatry', viz. that the only meaningful way of doing psychiatrical research, and consequently, the only acceptable concept formation in psychiatry is that of an existentiallsocial fenomenological approach.