I liked the Thomistic article, not only because it is Thomistic, but because it tackles the issue with a more complete treatment than just the issue of intoxication (which is never the only circuмstance in evaluating the liceity of MJ: If it were, medical marijuana would often be deemed illicit in circuмstances in which it is clearly licit).
Your use of "clearly" dramatically misrepresents the facts. There
seem to be
correlations that, when analyzed are
not causality. The salient example is one already mentioned: the correlation of schizophrenics and MJ use is not causal. Another common methodological flaw is either (1) having no control group at all or (2) using an unrepresentative and inappropriate control group (sort of like the Jєωs who compare the IQ of Jєωιѕн physicians to the IQ of welfare non-Jєωs to "prove" Jєωs are geniuses).
I'd like to underscore a point that I made early in the MJ tsunami.
You are correct, Sean, that loss of reason is not the only determinant of the moral liceity of medical and/or social use of MJ.
An honest assessment of the risk/benefit ratio is pivotal. We are bound to avoid undue risk of self harm (extreme sports anyone?). That is why the medical research is relevant to discussion of social use of MJ.
Today's best evidence is that
compared to alcohol, MJ has a much more favorable risk/benefit ratio, so, as best we can say
today, MJ use medically and socially is morally licit within the confines of pernennial, unchangeable, and infallible Catholic moral theology.
Q.E.D.