In a recent post, ‘The Unbearable Lightness of Philosophy’, http://backreaction.blogspot.ca/2016/08/the-unbearable-lightness-of-philosophy.html?spref=tw,
physicist Sabine Hossenfelder takes a stab at the physics-philosophy antagonism
that seems to be on the upswing. The
piece has some interesting observations, and appears to be intended as
something of a peacemaking exercise, but it contains two curious claims. I want to comment briefly on each.
First, she notes that the philosopher of science Massimo
Pigliucci has argued that philosophy of science doesn’t exist to advance the
work of scientists; rather, as a branch of philosophy, it exists to advance
philosophy; I agree. Philosophy of
science is philosophy, after all, and
its main goals are philosophical understanding of the world, in this case, the
workings and results of science.
Hossenfelder briefly dismisses this as follows: “Philosophy, hence, isn’t just useless, but it’s
useless on purpose. I applaud. At least that means it has a purpose.” This is very odd or, at least, tendentious
since it basically assumes that the only real use that something could have is
that of advancing science. But what is
the defence of that claim? Hossenfelder
offers none, but it would be interesting to see why it is the case that, for
example, advancing justice, reducing poverty, increasing access to art, or
sport, or whatever else, must ultimately be judged as useless simply because it
is not in the service of advancing science.
Surely this has to be wrong: there are many useful purposes other than
aiding scientists in their valuable – usually, anyway – work. One of these may well be philosophical
understanding. Of course it is possible
that philosophical understanding is useless, but it can hardly be assumed that
this is so simply because it fails to address the questions that most interest
working scientists.
Secondly, she comments on an interesting article by Tim
Maudlin, who defends the relevance of philosophy for science as a result of its
attention to conceptual and logical detail, which can help us understand “what follows
rom what” and, therefore, what a mathematical model means for our understanding
of the natural world. Attention to
semantic and logical detail means that explanatory or theoretical gaps can be
spotted and alternative proposals can be suggested for filling them; philosophy
has an imaginative component to it that can help create new lines of
thinking. Again, I agree. Hossenfelder replies: “If you want to know ‘what follows from what,’
as Maudlin writes, you have to convert language into mathematics and thereby
remove the ambiguities. Unfortunately, philosophers never seem to take that
step, hence physicists’ complaints that it’s just words.”
Now this is a very curious reply for a variety of
reasons. Consider that the extent to
which language and thought can be modeled mathematically is a very profound,
interesting, and puzzling question that has occupied philosophers for centuries
(think Pythagoras, Leibniz, Frege, and Russell, for a sample). Indeed, the tradition that grew out of the
work of Frege, Russell, and the early Wittgenstein, which came to be known as
“analytic philosophy”, is largely founded on the idea that mathematical logic
is the appropriate set of tools for modeling natural language. Much philosophy since then has been the attempt
to evaluate, critique, and advance this very project. Philosophers such as David Lewis, Timothy
Williamson, and Saul Kripke have helped us to understand the extent to which
modal logic can model counterfactual and subjunctive reasoning. Philosophers such as Arthur Prior and Michael
Dummett helped us uncover the logic underlying temporal reasoning. Philosophers such as Graham Priest and J. C.
Beal have advanced our understanding of the relationship between non-standard
logics and human reasoning in a variety of arenas. And so on, and so on.
Rather than giving us reason to turn away from philosophy as
useless, this response of Hossenfelder’s seems, rather, to give us plenty of
reason to expose ourselves to philosophical work of the past 100 years or so
and to continue the project of formalizing ordinary language and thought. The attempt to employ formal systems to model
everyday thinking and speaking is the attempt to make such thought and language
mathematically precise. Many recent and
contemporary philosophers are engaged in precisely this project which, if
successful, could represent a significant rapprochement between philosophy and
science. In short: successful, formal
models of language could be the contact point between philosophy – and other
disciplines, such as linguistics – on the one hand, and math and science, on
the other. That is, I think, a worthy
project to pursue and one that has shown much promise.
However, despite the precursors in Pythagoras and Leibniz,
“formal philosophy” in its current incarnation is still relatively young, just
over 100 years old. There remains a
great deal to be explored and uncovered.
There is even more work to be done in connecting formal models of
language and thought to mathematical models of the physical world. So I think Hossenfelder is wrong to suggest
that philosophers never take this step; they often do. It is just that the work is still in its
relative infancy, often disputed, and needs concentrated effort to
continue. I also think, further, that
she and other physicists are wrong to suppose that this is all “just words”:
language is the medium by which we express and understand ourselves;
understanding it correctly is of vital importance. The philosophers I mention above, and others,
are not playing with language in any trivial sense; they are working to understand
it, with as close to mathematical precision as is possible. If anything, they are working to advance the
interests that Hossenfelder is expressing.
So, I think that a proper understanding of this branch of
philosophy should, if anything, bring the physicists and philosophers closer
together.
