Steve3007 wrote: ↑September 27th, 2018, 9:57 am
On the other hand, if metaphysics refers to concepts that have no connection, either directly or indirectly, with that which can be empirically observed, then physics has no use for it at all. It is a basic principle of physics (and science in general) that all propositions that purport to be about physics must be falsifiable/verifiable. In other words, it must be possible to describe an observation by which they can be tested.
I think even with this definition physics definitely includes metaphysics. Physicists and cosmologist with regularity explore ideas and even present theories and hypotheses that cannot be tested (now at least) empirically. Multiverses, for example. A time may come when such things can be tested, and it is useful to allow exploration of possible solutions to problems or anomolies even if these cannot be tested. But further I think any system will have assumptions, that is metaphysical ideas, built in that cannot be tests. i wish I was smart enough to bring in Gödel's theorum, but wihtout it I can still point to things like 'there are natural laws' 'everything is physical' which cannot be tested, at least not completely, but function as useful axioms for methodology or a conclusion based on incomplete evidence, but still useful, in the latter case. We can see this in the latter case where the category 'physical' has expanded to include 'things' that are completley unlike what would have been considered physical a couple of hundred years ago. The metaphysical category is expanding.