If they actually have no logical basis then it would be hard to expect that they would be better than random.
But a feeling that something is likely true is a logical basis, since it is caused by something, and it could be a reason why someone can make correct judgments at a rate better than random. For example, when I tried calibration games, whenever a binary question came up and I had no knowledge of the topic, I guessed based on what I happened to feel was more likely. So for example if the question was "Did team A or team B win the superbowl in 1984?" I had no knowledge of the answer because I am not interested in sports and pay no attention to them. But one of the team names might have felt slightly more familiar than the other, and so I guessed that name.
Following that policy of following my feelings, I was not able to get less than 60% accuracy on the binary questions that I had no real knowledge about.
I interpreted that sentence to mean that the belief itself has no logical basis, not the judgements.
From the standpoint of treating a human being as a rational agent, it makes absolutely no difference whether a judgement is based on feeling, belief, intuition, divine inspiration, etc. All that matters is the decision and the outcome.
I spent an hour recently talking with a semiotics professor who was trying to explain semiotics to me. He was very patient, and so was I, and at the end of an hour I concluded that semiotics is like Indian chakra-based medicine: a set of heuristic practices that work well in a lot of situations, justified by complete bullshit.
I learned that semioticians, or at least this semiotician:
When I've read short, simple introductions to semiotics, they didn't say this. They didn't say anything I could understand that wasn't trivial. I still haven't found one meaningful claim made by semioticians, or one use for semiotics. I don't need to read a 300-page tome to understand that the 'C' on a cold-water faucet signifies cold water. The only example he gave me of its use is in constructing more-persuasive advertisements.
(Now I want to see an episode of Mad Men where they hire a semotician to sell cigarettes.)
Are there multiple "sciences" all using the name "semiotics"? Does semiotics make any falsifiable claims? Does it make any claims whose meanings can be uniquely determined and that were not claimed before semiotics?
His notion of "essence" is not the same as Plato's; tokens rather than types have essences, but they are distinct from their physical instantiation. So it's a tripartite Platonism. Semioticians take this division of reality into the physical instantiation, the objective type, and the subjective token, and argue that there are only 10 possible combinations of these things, which therefore provide a complete enumeration of the possible categories of concepts. There was more to it than that, but I didn't follow all the distinctions. He had several different ways of saying "token, type, unbound variable", and seemed to think they were all different.
Really it all seemed like taking logic back to the middle ages.