To begin with, there's no evidence, from either a general web search or a THOROUGH search of the UC-Irvine site, that Belladonna is receiving an honorary degree of any kind. And that sort of thing would be BIG news. Departments invite speakers all the time; it's entirely possible the psychology department invited to her to talk about why she's not bothered by taking it up the ass on camera... whereas most people would be.
Beyond that, however, there's no evidence I can find that she's speaking AT ALL. Which means, if she is, then this is not even a major event. In other words, not the kind of thing that would be held in an auditorium - that's the sort of event you advertise, if only because you sunk enough money into using the building that you want SOME kind of jusification for it. More like what I suggested above, a small, departmental talk. Maybe twenty, thirty people in a seminar room in the Social Sciences Building or whatever? Hardly a big deal.
Besides, though, I don't see why it would necessarily be the case that she wouldn't have anything to say. Careena Collins and Mike Lucas have a law degrees. Sharon Mitchell is a PhD. Several of these girls went to college. Even the ones that didn't might have reflected on their lives as porn stars enough to have something interesting to say. Hell, Jenna Jameson wrote a book (yes, it was co-written with that Strauss guy, but while Strauss may have been cleaning up the presentation, he sure didn't contribute the content... I've read some of his other stuff. You can tell) and Nina Hartley has a vivacious career as a public speaker.
Assuming they have nothing to say because they work in porn is to assume that there's something wrong with them because they work in porn. I wouldn't guess they're any more fucked up than anyone in the entertainment industry. Although, after having spent most of my life in Nashville, I am prepared to say that the entertainment industry people are plenty screwed up on the whole as it is.
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Pornography is supposed to arouse sexual desires. If pornography is a crime, when will they arrest makers of perfume? ~Richard Fleischer