Is philosophy ultimately a paradigm - a set of self-consistent ideas that are based upon one or more assumptions? If not, why not and what is it?

There is no one paradigm that all philosophers share. Philosophy is a discipline in which people search for paradigms.

The idea that scientific researchers are trained to work within a paradigm originates with Thomas Kuhn. For Kuhn, a shared paradigm makes normal science possible. Across the globe, researchers are trying to develop a vaccine for a disease. They pursue different avenues of research, but they all share a set of ideas about how viruses are spread, why they cause certain symptoms, what kind of vaccines are likely to be effective, and what kind of experimental results will demonstrate that a particular vaccine shows promise. The lead researcher in one team has five different vaccines to test. He selects five graduate students and instructs each to test one of the vaccines, following the same protocols. Because the students are well trained, it makes no difference whether he assigns Student A or Student B to carry out the test on Vaccine 1. They will both follow the same protocols exactly. This is normal science: a vast cooperative enterprise.

The researchers do not all have exactly the same theory. At any time, there might be competing ideas about how a particular vaccine in spread, or about how in interacts with the immune system. But their shared paradigm means that there will be consensus about how to interpret decisive experimental results that establish that one theory is better than another. All the researchers share certain key concepts - they know what a virus is, what RNA is, what the immune system is, and so on. In science, research papers frequently have a whole team of authors. Someone who enrols in a Ph.D. program frequently becomes part of a team of researchers involved in some shared project.

Philosophy isn’t like that. Sometimes two philosophers will produce a paper or a book together, but single authorship is still more common. There area also plenty of books or journal issues where several philosophers cooperate by writing about a problem and responding to each others’ proposals. The reason philosophers do not collaborate like scientists is not that philosophers are unsocial (although some are) but because when philosophers meet, the result is more likely to be an interesting disagreement than teamwork based on a methodology that both accept. Scientists researching on vaccines share the concept of a virus. Philosophers are still arguing about what a concept is.

Of course there have been many attempts to make philosophy more scientific. Sometimes this results in useful work. For example, a lot of very important work in mathematical logic was carried out by people hoping to answer philosophical questions - for example, do mathematical objects exist? That work in mathematical logic has important applications in computer science. But do mathematical objects exist? The jury is still out. When I say that the jury is out, I don’t mean that nobody claims to have an answer. My own conclusion is that mathematical objects don’t exist. But there is no consensus, and no consensus about how to reach a consensus.

But, to return to the original question, it is true that many philosophers do attempt to produce their own paradigm, in the sense of a set of self-consistent ideas based on shared assumptions. The late Nicholas Rescher examined what we might hope to achieve by this method. I’m now offering a quick summary of his main ideas based on what I remember - I don’t have the time to go through my notes and offer a proper introduction.

I try to think consistently about a wide variety of issues. I ask whether numbers are real, whether God is real, and whether money is real, and then think about how different senses of reality are connected to produce a theory that is consistent. In doing so, I discover that I am relying on a lot of assumptions, assumptions that are made explicit as I try to clarify the connections. Some of those assumptions I might reject, but some I simply cannot reject - to reject them would be unthinkable, absurd.

But when different philosophers meet, they discover that they have rejected different assumptions, because they have different ideas about what is obviously absurd and what assumptions are basic to the very process of thinking. Nihil tam absurdum dici potest ut non dicatur a philosopho - there is no so absurd that it hasn’t been said by some philosopher (Cicero). But it is the job of philosophers to consider absurd ideas, just in case they work out.

For an example of how this work, consider modal logic. Kripke’s brilliant mathematical mind came up with a framework for semantics that provided definitive answers to a lot of questions about rival systems of modal logic. There’s a paradigm for you! But immediately, this raises a question. Kripke’s framework involves “possible worlds.” A possible world assigns a truth-value to every proposition that you have, that much is clear. But what exactly does that mean? Within a few years of Kripke’s first papers on the topic, it was clear that there was a huge gulf between his way of thinking about possible worlds and that of David Lewis. For Lewis, all possible worlds are equally real. The “actual” world is just the possible world that is real to us because we are in it. For Kripke, the actual world is the real world, other worlds are stipulated, not explored with some philosophical telescope. For many philosophers, Lewis’ theory appeared blatantly absurd, but he responded that he could not refute an incredulous stare, and challenged people to produce arguments against his position. Kripke’s framework did not become a shared paradigm for philosophers to settle questions, it became itself a topic of philosophical debate.

But, following Rescher, there is something that emerges from this kind of disagreement, not consensus, but self-knowledge. I realize that I can never accept your conclusions because they violate some assumption that is bedrock, as far as I am concerned. Here I stand, I can do no other (the words attributed to Martin Luther).

Kuhn’s concept of a paradigm was inspired by Wittgenstein, he was talking about the role of paradigms in learning a language. Amo, amas, amat. I love, you love, he she or it loves. Amo is commonly used as a paradigm verb when learning Latin. The paradigm is used to teach beginners. Young scientists learn the paradigm that researchers share so that they can join the research community.

Philosophers work towards building a coherent set of ideas, something that looks very much like a scientific paradigm. But this is not the starting point, it is the end product. It is not shared, it is usually unique to each philosopher.