system
Given the following post, respond as if you're commenting on Reddit:
human
What can Scientific Realists believe?

It seems like all of the contemporary versions of Scientific Realism still significantly limit what we can justifiably believe about the world, at least when compared to the commonsense view. Take a statement like:

>"\[electrons, quarks, bosons, black holes, etc.\] exist"

**Structural Realism**: Unjustified. We can't know anything about theoretical entities, either because we just lack epistemic access to them (ESR) or because there aren't any entities at all (OSR)

**Entity Realism**: Depends. While belief in experimental entities used to manipulate other phenomena, like electrons, photons, and protons can be justified (although even then, belief in the theoretical properties of these entities is still unjustified), other theoretical entities, like quarks, gluons, W and Z bosons, Higgs bosons, and a wide range of theoretical astronomical and cosmological posits like black holes and the big bang will fail to be justified because we have not used them experimentally to manipulate other phenomena.

**Deployment Realism**: Unjustified. We can't know what the true components or working posits of a theory are until it has been superseded, so we don't have the license to believe in the existence of any particular entities posited by our theory, only that some posit will be carried over into the next theory.

**Perspectival Realism**: Unjustified. We can only say "Theoretical entities exist when *contextualized* within our current scientific perspective".

**Minimal Realism(s)**: Unjustified. We can only say that our current theories are "truer" than our past theories, but they may still be very far from the truth.

On all of these views, we must be agnostic about whether large parts of our scientific knowledge are actually (approximately) true. They don't really sound that different from antirealism when compared to our commonsense view. **So my question is, am I right in thinking this? What can scientific realists believe? Are there scientific realist positions that preserve a robust amount of scientific knowledge?**

Sorry for any possible mischaracterizations of these views.
gpt
Forget about all these different versions of scientific realism. 

The scientitic realist says that, at least in some cases, we have reason to believe that the entities included in a strongly supported scientific theory actually exist. The scientific anti-realist denies this. For example, the instrumentalist will say that talk of electrons is a useful fiction for talking about certain observable phenomenon, but there aren't really such entities.

So, what entities can a scientific realist believe? Whichever she thinks are well-supported by the evidence! The issue here is that most of us think that science isn't finished. Maybe some new discovery will force a paradigm shift. Realists can disagree among one another about what sort of entities they're willing to post exist, and what the standard is for making such a posit. But, if you're a scientific realist and you think our current picture is close to correct, it would be reasonable for you to assert that existence of most or all of the entities posited by current scientific theories.