What is wrong with expressing one's opinion on things? Intelligent people often have opinions on a lot of things which are outside of their formal area of expertise. Those opinions may sometimes (even often) turn out to be wrong, but can nonetheless make for some interesting conversations. They may sometimes say some things which sound stupid to the real experts in the field, but a genuinely intelligent person is open to taking those expert objections thoughtfully and seriously, as opposed to your garden variety crank or conspiracy theorist who can't even understand those expert objections, but doesn't need to understand them to know that they are wrong.

The other day I was having a discussion about psychiatry with a relative of mine who is an esteemed psychiatry professor. Now, no doubt about it, he knows heaps of things about psychiatry which I, as a non-psychiatrist, don't. But, on the other hand, the conversation made me realise I know some things about his field he doesn't: I read and am interested in psychiatrists who criticise "mainstream" approaches (such as by attacking the DSM, whether in general or with respect to specific diagnoses included in it or both), and so I know a lot about who those people are and what their publications and arguments are, and what the "mainstream" responses are. He is far less interested in that topic, so it appears to me he only knows those criticisms at a relatively high level, and that he isn't across the details of them to the extent that I am. I think he generally trusts that the mainstream approach is right, and focuses (both as a researcher and as a clinician) on working within it rather than questioning or challenging it.

Does the fact that he is an esteemed professor of psychiatry and I have no formal qualifications or professional experience whatsoever in this field or any related field mean that he is (likely to be) right and I am (likely to be) wrong? Well, I think debatable areas of expert opinion, just because you happen to personally know an expert on one side of that debate, doesn't make that side automatically the right side. Even acknowledging that there is a majority and minority side to many of these debates, I think often the minority may be a minority, not because their actual arguments are weaker, but due to social and cultural and historical and political factors. That is especially true in fields such as psychiatry, which still have a rather weak empirical basis. Or, you could say the same about theoretical physics, which starts with a very firm empirical basis (experimental physics is at a far more advanced stage than neurobiology/psychology/etc) but wants to go a long way beyond it – just because string theory is more popular in the contemporary theoretical physics community than loop quantum gravity, is not good evidence that the former is more likely to be true than the later. It is important here to distinguish respectable minority views within academia (even if small minorities) from truly fringe/crank views (which few academics would consider worthy of respect). I also think my esteemed-psychiatry-professor-relative would be more likely to convince me to abandon my view of the topic in favour of his, if this was an area of his field of which he'd developed a detailed knowledge, as opposed to it being an area of which he only appears to know at a high level.

And now when we come to PG expressing views on aesthetics, which is commonly viewed as a branch of philosophy – philosophy is an area which is especially unsettled, and in which the question of where the majority of academic opinion lies is especially distant from the question of what is likely to be true. I suppose the main way I'd fault PG here, is there is a lot of pre-existing academic work on this question, and he doesn't engage with it at all, or display any knowledge of it. On the other hand, maybe given the constraints of the format of the talk he was asked to deliver, the likely interests and abilities of the audience, etc, attempting to engage with that work (to the extent that PG knows it) was not really going to be possible.