So far, all I've got is below, which seems to be a quote in a chat under an article. Chomsky's potential words are in inverted commas, with the introductory paragraph being from the poster:
As for the race & IQ debate. I suppose you are referring to Chomsky’s dismissal of Richard Herrnstein’s IQ. In fact questioning the propriety of some particular scientific investigation is *not* equivalent to a call for the *banning* much less of punishing such an investigation. I can see no double standard just common (left-libertarian) sense. There would have been equivalence had Chomsky suggestes banning Herrnstein’s article or firing him from his university position. This was not the case. The relevant quote regarding Chomsky’s criticism of Herrnstein’s IQ is this:
“… the question of the validity and scientific status of a particular point of view is, of course, logically independent from the question of its social function; each is a legitimate topic of inquiry, and the latter becomes of particular interest when the point of view in question is revealed to be seriously deficient on empirical or logical grounds.
… (The scientist) is responsible for the effects of what he does, insofar as they can be clearly foreseen. If the likely consequences of his “scientific work” (can be used as a justification for class and caste hierarchies), he has the responsibility to take this likelihood into account. This would be true even if the work had real scientific merit-more so, in fact, in this case.
Similarly imagine a psychologist in Hitler’s Germany who thought he could show that Jews had a genetically determined tendency toward usury … or a drive toward antisocial conspiracy and domination, and so on. If he were criticized for even undertaking these studies, could he merely respond that “a neutral commentator … would have to say that the case is simply not settled” and that the “fundamental issue” is “whether inquiry shall (again) be shut off because someone thinks society is best left in ignorance?” I think not. Rather I think that such a response would have been met with justifiable contempt. At best he could claim that he is faced with a conflict of values. On the one hand, there is the alleged scientific importance of determining whether, in fact, Jews have a genetically determined tendency toward usury and domination (as might conceivably be the case). On the other, there is the likelihood that even opening this question and regarding it as a subject for scientific inquiry would provide ammunition for Goebbels and Rosenberg and their henchmen. Were this hypothetical psychologist to disregard the likely social consequences of his research (or even his undertaking of research) under existing social conditions, he would fully deserve the contempt of decent people. Of course, scientific curiosity should be encouraged (though fallacious argument and investigation of silly questions should not), but it is not an absolute value.”