A brief look at the sequence further belies the significance of the postulated “stages”. (1) Indeed, unsurprisingly, the use of any substances is preceded by non-use (the only truly invariant step of the sequence). It is the non-use then, which, by the logic of the “majority have previously used . . .” line of thinking, should be the actual gateway condition. (2) The first use of illicit drugs is frequently preceded by consumption of licit substances. Following the logic of the current implementation of the gateway theory, it is then alcohol and tobacco use rather than marijuana and “hard” drugs that need to be prevented, because once the licit outset of the sequence is barred, there should be no danger that the rest of it will materialize. Common sense and experience, however, suggest otherwise. (3) The initiation order is frequently reversed even for the licit-to-illicit sequence, in contradiction to the stated first validity criterion of the GH. This order becomes even less consistent beyond involvement with illicit substances, to the degree that the use of illicit drugs other than marijuana,
