My last post ended on a note that deserves more explanation.
Scientific realism is the view that science describes the world as it actually is (or approximately as it is, for weak forms of scientific realism). There are however, some criticisms of this view.
The first is underdetermination. When multiple, conflicting theories are all consistent with the data, there is no evidence for believing one theory over another. And since they conflict, they cannot both be true.
The next is known as “skepticism about inference to the best explanation”. It builds off of a possible realist response to underdetermination: It’s fine if multiple theories are consistent with the data, since one will explain the data better, meaning that it is true.
One problem with that approach is defining what characteristics make one explanation better than the other. Another, is do those characteristics make one theory more true than another?
A third is the pessimistic induction, which takes a different view. Consider all past scientific theories that have been replaced. The past theories must be considered false in the present. So what’s to say that in the future, we won’t be saying the same thing about current theories?
Each of these arguments sheds some doubt on the view that science describes truth. And yet, scientists mostly go ahead under the assumption that it does. In truth, whether or not science describes the universe as it actually is doesn’t matter to the practice of scientists. Whether or not theories are true, they are enormously successful in allowing us to build things that we couldn’t dream of even 100 years ago.