“Given a model that predicts accurately, what would you do differently if the objects described in the model do or don’t exist at some ontological level? If there is no difference, what are we worrying about?”
If I recall correctly he abandons that particular rejection when he gets an actual answer to the first question. Specifically, he argues against belief in the implied invisible when said belief leads to making actual decisions that will result in outcomes that he will not personally be able to verify (eg. when considering Relativity and accelerated expansion of the universe).
(2) the ontological status of objects that, in principle, could never be observed (directly or indirectly)
I took shminux as trying to duck the first debate (by adopting physical pragmatism), but I think most answers to the first question do not necessarily imply particular answers to the second question.
If I recall correctly he abandons that particular rejection when he gets an actual answer to the first question. Specifically, he argues against belief in the implied invisible when said belief leads to making actual decisions that will result in outcomes that he will not personally be able to verify (eg. when considering Relativity and accelerated expansion of the universe).
I think you are conflating two related, but distinct questions. Physical realism faces challenges from:
(1) the sociological analysis represented by works like Structure of Scientific Revolution
(2) the ontological status of objects that, in principle, could never be observed (directly or indirectly)
I took shminux as trying to duck the first debate (by adopting physical pragmatism), but I think most answers to the first question do not necessarily imply particular answers to the second question.
I am almost certain I am saying a different thing to what you think.