Btw I see these examples as dragons on the edge of the map - I think clustering features together is a useful strategy until we can isolate some features as causal. It is also crucial to be transparent about the status of the concepts we invoke both in research and clinical practice.....

Flippers and convergent evolution might be a good (?the best?) example of the same observable features having different causes - I'm not that up on biology either! What about "aliens building pyramids"?

Perhaps the problem here is not with dimensional models but with woolly clinical thinking?

Is one way through this checking that we have described potentially overlapping symptoms in sufficient detail/granularity so that they are indeed the same symptom? Eg is the dolphins flipper exactly the same as the turtles?

I see so much confusion (eg syndromes reified as “natural kinds”) that I appreciate the effort to push the syndrome model of covarying symptoms as far as it can go and then testing if it gives us a better basis to search for shared etiology. If it were easy we’d have solved it by now?

Unlearn avian adaptation to urban environments?

Displacing the Ibis?

And does it matter if we dont have equal granularity across symptoms? Actually I think the hi in hitop allows some elegant zoom in and out to different levels of granularity.

What do you think about the granularity of the symptoms? Do we need more work to get our “indivisible atoms” or is that fraught and we are stuck with some kind of linguistic relativism (eskimos having many words for snow) and does that matter for structure? Love your work!