Richard Price

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Nov 11, 2012

One Hypothesis About the Role of Philosophy

I sometimes find myself in conversations discussing the role of philosophy. Over the years, I have formed a view of the role of philosophy, and I wanted to share it. My background is that I did a PhD in philosophy at Oxford, where I was a Fellow of All Souls College. I finished my PhD in 2007. 

These observations below are based on my experience talking about the role of philosophy with other philosophers, together with a few of my own reflections. As such this post is not a rigorous piece. It is more like a statement of a hypothesis, based on anecdotal reflections about philosophy’s history. I am hoping that, by airing this hypothesis, people who know aspects of these matters better than me can come along and add their thoughts and criticisms. 

Philosophy’s role in spawning new disciplines

The hypothesis is that one of the principal roles of philosophy is in spawning new disciplines. In this role, philosophy takes a new terrain where there has not been much work, and brings it under theoretical control. Eventually some questions emerge that are precise enough to warrant empirical investigation. 

There was a time, 2,500 years ago, where very little was under theoretical control, and philosophy, as practised by people such as Aristotle, covered more or less everything. Then some areas, such as physics, biology, and chemistry became precise enough that they spun out as separate disciplines. Some recent disciplines to have emerged out of philosophy include economics and psychology. Modern linguistics may have been influenced by philosophy too. 

Predicting the spawning of new disciplines

The birthing process of a new discipline takes many decades, so it’s very hard to predict what disciplines, if any, are being birthed by philosophy right now. When economics and psychology were in the process of being birthed, the people involved in the process probably couldn’t predict that the new questions they were exploring would provide the foundations for entire new disciplines.

Similarly, decision theory is a relatively new field, and it’s the intersection of work in economics, statistics, and formal epistemology. It’s very hard to predict whether this nascent field will grow into a discipline the size of economics. We don’t know what will happen to it. 

Another thing that makes it difficult to predict what disciplines philosophy will spawn next is that philosophy also spawns new sub-areas of philosophy every so often. For instance, philosophy of language is a relatively new area of philosophy, one that emerged in the early 20th century from the work of Bertrand Russell, Gottlob Frege, and Ludwig Wittgenstein. Philosophy of language applied some theoretical rigor to the structure of language, a few decades before the birth of modern linguistics, as pioneered by Chomsky

The spawning process: examples from economics, psychology, and decision theory


Philosophy often seems terribly abstract. Moral philosophers debate, amongst other things, about whether there is such a thing as objective good and objective bad, or whether all moral judgements are just subjective likes and dislikes. Some people consider this an important question in and of itself, whereas others are not moved by it.

Be that as it may, occasionally an abstract topic like this will spawn a new discipline. Adam Smith, who is considered the father of economics, was a moral philosopher, who took the abstract questions of moral philosophy in a new direction, creating the foundation of a new discipline in the process. 


The study of consciousness and the mind also seem extremely abstract. Philosophers of mind try to map out the various mental states that we find ourselves in, and try to figure out how those mental states interact with one another. William James, who is considered the founding father of psychology, was a philosopher and a physiologist, who took traditional philosophy of mind questions in a new direction, spawning a new discipline in the process. 

Decision theory

Another traditionally very abstract part of philosophy is epistemology, which is the study of knowledge. Epistemologists ask questions such as whether we know anything. One central issue at the heart of epistemology is the idea that our internal visual and sensory states might have been caused by a number of possible external circumstances. They could have been caused by real world objects, such as tables and chairs - i.e. the sorts of objects we believe cause our experiences. Or they could have been caused by a computer that we are hooked up to, as in the Matrix. There are infinitely many possible causes of our internal visual states. How can we know which of these infinitely many possible causes actually caused our visual states on a given occasion?

As with ethics, some people consider this an important question in and of itself, and others are not moved by it. But, be that as it may, one aspect of epistemology that has grown considerably in recent decades is formal epistemology, which is a branch of epistemology, and which studies questions such as how people should update their beliefs in response to new evidence. Formal epistemology is one of the contributing fields to decision theory. Ultimately, we want computers to be able to make decisions with human-like intelligence, so modeling out human decision-making practices is an important first step. 

Progress in philosophy

People often say that there is no progress in philosophy. One way of thinking of the progress in philosophy is that once enough progress has been made in a given area, that sub-area is spun off into an entire new discipline, as in the cases of economics or psychology. 

We haven’t answered some of the central questions in philosophy, such as “Do we know anything?”, and “Is there objective good and objective bad?” But we have made progress in mapping out some of the conceptual terrain around these questions. Some of this progress is manifested in the emergence of disciplines that are focused on specific aspects of these questions. 

The continuing role of theory

It is also worth pointing out that once a new discipline has been spawned, there remains a lot of theoretical work to do. The theorists who do this work are not in philosophy departments, but their work is often highly philosophical in nature. 

In the early days of a new discipline, there will be continue to  be collaboration between theorists in the new discipline, and philosophers. Decision theory is at this stage right now, and there continues to be some collaboration between philosophers and theorists in economics, psychology, and linguistics. 

In other areas, such as physics, the theoretical parts are so large and established that there is no longer collaboration with philosophy. In the case of physics, the influence is now the other way: philosophers of physics take insights from theoretical physics, and bring them back into philosophy to see what ramifications they may have for philosophical theories. 

How philosophy decides what to work on

How does philosophy decide what to work on? It definitely isn’t with a view to spawning a new discipline. No-one would know where to start if that was the guiding goal. Generally the motivating idea in philosophy is to take ordinary concepts that we seem to use a lot, and see if they withstand scrutiny. 

Identity over time

For instance, someone might say “Beside me now is the woman that I married 25 years ago, to this day.” In this remark is the assumption that the woman he is married to now is the same person as the person he married 25 years ago, and that she is a different person from his mother, or his sister. He is assuming that there is such a thing as identity over time. One aspect of metaphysics is focused on taking this notion of identity over time, something that underlies the way we speak, and seeing what it comes to. What is the implicit theory of identity over time that we seem to believe, and does the theory withstand scrutiny?

Free will

Another question concerns free will. We think of ourselves as free agents, and different in kind from a plant, which just responds to external stimuli reflexively, and not by choice, or by the exercise of willpower. But what is free will? If you were a god, creating a new universe, and you said “In this new universe, people will have free will”, what are you granting people exactly? What does it mean for that command to be properly implemented? The study of free will is about answering these kinds of questions. 

Similar points apply to our conception of good and bad, and our conception of knowledge and justification. These are concepts that we regularly deploy in describing how we think of the world around us. Philosophy’s role is to try to extract the underlying theory that we seem to operate with, with regard to these concepts, and then see if those theories withstand scrutiny. 

Every so often, as theoretical rigor is applied to these concepts, and their underlying commitments, an area pops up where questions have been sufficiently defined for them to be studied on their own, using a wider variety of tools: mathematics, experiments, and different kinds of theorizing. That area may fizzle out, or it may be the beginning of a new discipline.