Berlinski is one of the movers and shakers of the contemporary creationist movement, associated with the Discovery Institute and one of their most frequent and famous debaters. A delusional, pompous narcissist with an ego to fit a medieval pope. Also a name-dropper (most of his talks concern important people he has talked to). A comment on one of his lunatic self-aggrandizing rants can be found here (sums up this guy pretty well):
He is apparently really angry at evolution (it is unclear why), and famous for his purely enumerative “cows cannot evolve into whales” argument.
Berlinski was once a moderately respected author of popular-science books on mathematics. He can still add numbers together, but has forgotten the GIGO rule (“garbage in, garbage out") of applied mathematics. Some of his rantings are discussed here.
Likes to play ‘the skeptic’ (which means denialism in this case, and that is not the same thing).
Diagnosis: Boneheaded, pompous and arrogant nitwit; has a lot of influence, and a frequent participator in debates, since apparently the Discovery Institute thinks that’s the way scientific disputes are settled (although he often takes a surprisingly moderate view in debates, leading some to suspect that he is really a cynical fraud rather than a loon).
(for a nice description of the difference between skepticism and paranoid denialism, I recommend these three articles: here, here, and here.)