[tsimionescu]

Yes, Roger Penrose, despite his extraordinary career and contributions to science, has more recently been engaging more in this type of pseudoscience.

It can and has happened to other extraordinary minds as well - Linus Pauling, one of the forefathers of quantum chemistry and molecular biology, but also a promoter of vitamin C as a panacea in his later years.

[cscurmudgeon]

> pseudoscience

Repeatedly calling something pseudoscience doesn't make it so.

[gaganyaan]

You're rather missing their point. Great minds have fallen for pseudoscience. Why should we think Penrose is any different?

[tsimionescu]

GP asked whether we are calling what Roger Penrose is doing pseudoscience, and I responded that we do.

Now, why is it pseudoscience?

Because the parts of the theory due to Penrose are essentially philosophical, he doesn't really make any firm claims beyond "quantum effects - particularly superposition - are involved in human decision-making". The parts that Hameroff brings to the table are specific, but fanciful. The whole "microtubules observe quantum effects" is about as plausible as cold fusion - it is motivated thinking that contradicts some basic limits that we have observed, and relies on some gaps in our physical knowledge to not quite be provably wrong.

Overall they are combining musings about the universe with bits of biology and QM that are not yet fully understood into a theory that uses the trappings of science, but relies on motivated thinking to have any plausibility. It's most similar to the homeopathic quacks' claims about the memory of water: not fully proven to be impossible, but moatly on account of the vagueness of the claims. So, what they are doing fits the definition of pseudoscience.