This post isn’t really a response to John. I shall also be referencing the Wikipedia page and the SEP page on scientific realism. I am puzzled by the discussions of scientific realism, so I’ll be illustrating that puzzlement.
The Wikipedia page begins with:
Scientific realism is, at the most general level, the view that the world described by science is the real world, as it is, independent of what we might take it to be.
That sounds about right to me. And, with that as a definition, I could call myself a scientific realist. But, as I read further in that Wiki page, I begin to run into statements with which I cannot agree. In discussion on other internet sites, I have had philosophers suggest that I am anti-realist, though that seems wrong to me. So perhaps you can see that I might find it all a bit puzzling.
Early in the SEP page, I read:
It is perhaps only a slight exaggeration to say that scientific realism is characterized differently by every author who discusses it, and this presents a challenge to anyone hoping to learn what it is.
Perhaps that helps explain my puzzlement.
God’s eye view philosophy
People who discuss scientific realism seem to hold to a God’s eye view philosophy. That seems to come across as an unstated assumption. They need not be theists, and they need not believe that there actually is any god. But they seem to the view that if there were an omniscient god, then that hypothetical god would have some particular view or description of the world. As I use the expression, a god’s eye view philosophy is just the assumption that one can talk as if there were such an ideal description.
As an example, John asks (rhetorically) in his realism video:
What does science mean? What does it imply? Are we just building nice pictures of the world which happen to help us, and there’s no connection to the way the world is.
So there’s that expression “the way the world is.” John takes that as meaningful, and that’s where I see him as assuming a god’s eye view philosophy. For myself, I don’t see how “the way the world is” could mean other than “the way the world seems to us.” Yet John’s question becomes pointless if we change the wording to “the way the world seems to us.”
Here’s my problem with a god’s eye view philosophy. Suppose that there are several omniscient gods who do not talk to one another. I cannot see any reason why those several gods would all describe the world in the same way. We know from our own experience that French people, Chinese people and English people have very different ways of describing the world. Why wouldn’t different gods also have different ways of describing?
Real vs. canonical?
One of the questions that John sees as important, is this: Are species real?
I find that puzzling. As far as I am concerned species are real enough. But it is far from clear to me that “real” means anything when applied to species.
This is an issue that came up earlier, when I agreed with those who say that species are conventional, and John disagreed. I wrote several posts related to that.
As best I can tell, a world in which species are real is not much different from a world in which they are not real. The only difference that I can see between those two worlds is a subtle change in the meaning of “real”. Since meanings are subjective anyway, this does not seem of any scientific importance.
Let me use an analogy from mathematics. I might want to look at the area around me as a two dimensional space. To do that, I pick two coordinate axes. I might choose an x-axis in an east-west direction, and a y-axis in a north-south direction. But I could just as easily choose an x-axis in a northeast direction and a y-axis in a northwest direction. The actual choice is arbitrary.
Mathematicians do not say that these axes are not real. Rather, they say that they are not canonical. In fact, mathematics proves that there is no canonical choice of axes (or direction vectors) to use.
Perhaps I am misunderstanding John. But I think that when he asks if species are real, his concern is whether they are canonical (in the mathematical sense of that word). But I don’t see how they could be canonical. It seems to me that they unavoidably depend on pragmatic but somewhat arbitrary human choices.
Comparison to evolution
Suppose we could rewind the tape of the world and let it play out again. According to one school of thought, we would finish up with much the same biosphere as we currently have. The belief is that evolution would converge toward a particular solution. It is my understanding that Dawkins holds a view along these lines.
Others, such as the late Stephen Gould and Larry Moran hold that there are too many contingencies, and that life would likely evolve in a very different way after that rewind.
Scientific realism seems to be based on something analogous to the convergence view that I have attributed to Dawkins, while my view of scientific change is more like the contingency view of Gould, Moran and others.
Realism and idealism
To me, reality is what I am dealing with when I pick up a handful of dirt, or when I pluck a fruit from a tree, or when I wash the bird droppings from my windshield. But scientific realism does not seem to be at all concerned with reality in that sense. Rather, scientific realism seems to be concerned with how well one set of abstract representations matches a putative other set of representations (those from the god’s eye view). The dirt and the bird droppings don’t seem to be involved. I suspect that Berkeley would have found scientific realism very congenial to his own idealism. Admittedly, scientific realists explicitly deny idealism, but apart from that explicit denial, they seem to be saying almost what idealism argues.