Last week, we explored how some of history’s greatest minds, including Richard Feynman, Carl Sagan, Albert Einstein, Marie Curie, and Isaac Asimov, defined science. Kant famously considered philosophy the “queen of the sciences” — whether or not that is true, philosophy seems even more elusive than science to define.

From Philosophy Bites, the book based on the wonderful podcast of the same name, comes an omnibus of definitions, bound by a most fascinating disclaimer — for, as Nigel Warburton keenly observes in the book’s introduction, “philosophy is an unusual subject in that its practitioners don’t agree what it’s about.”

The following definitions are excerpted from the first chapter of the book, which asks a number of prominent contemporary philosophers the seemingly simple yet, as we’ll see, awfully messy question, “What is philosophy?”

Philosophy is thinking really hard about the most important questions and trying to bring analytic clarity both to the questions and the answers.” ~ Marilyn Adams

[P]hilosophy is the study of the costs and benefits that accrue when you take up a certain position. For example, f you’re arguing about free will and you’re trying to decide whether to be a compatibilist or incompatibilist — is free will compatible with causal determinism? — what you’re discovering is what problems and what benefits you get from saying that it is compatible, and what problems and benefits you get from saying it’s incompatible.” ~ Peter Adamson

Philosophy is the successful love of thinking.” ~ John Armstrong

It’s a little bit like what Augustine famously said about the concept of time. When nobody asks me about it, I know. But whenever somebody asks me about what the concept of time is, I realize I don’t know.” ~ Catalin Avramescu

(Cue in Richard Feynman’s similarly-spirited answer to what science is.)

A few common themes begin to emerge, most notably the idea of critical thinking:

Philosophy is 99 per cent about critical reflection on anything you care to be interested in.” ~ Richard Bradley

I don’t think it’s any one thing, but I think generally it involves being critical and reflective about things that most people take for granted.” ~ Allen Buchanan

Philosophy is critical thinking: trying to become aware of how one’s own thinking works, of all the things one takes for granted, of the way in which one’s own thinking shapes the things one’s thinking about.” ~ Don Cupitt

Another running theme — sensemaking:

Most simply put it’s about making sense of all this… We find ourselves in a world that we haven’t chosen. There are all sorts of possible ways of interpreting it and finding meaning in the world and in the lives that we live. So philosophy is about making sense of that situation that we find ourselves in.” ~ Clare Carlisle

I think it’s thinking fundamentally clearly and well about the nature of reality and our place in it, so as to understand better what goes on around us, and what our contribution is to that reality, and its effect on us.” ~ Barry Smith

[Philosophy is] a process of reflection on the deepest concepts, that is structures of thought, that make up the way in which we think about the world. So it’s concepts like reason, causation, matter, space, time, mind, consciousness, free will, all those big abstract words and they make up topics, and people have been thinking about them for two and a half thousand years and I expect they’ll think about them for another two and a half thousand years if there are any of us left.” ~ Simon Blackburn

Also recurring is the notion of presuppositions:

Philosophy has always been something of a science of presuppositions; but it shouldn’t just expose them and say ‘there they are’. It should say something further about them that can help people.” ~ Tony Coady

Philosophy is the name we give to a collection of questions which are of deep interest to us and for which there isn’t any specialist way of answering. The categories in terms of which they are posed are ones which prevent experiments being carried out to answer them, so we’re thrown back to trying to answer them on the basis of evidence we can accumulate.” ~ Paul Snowdon

Philosophy is what I was told as an undergraduate women couldn’t do* — by an eminent philosopher who had best remain nameless. But for me it’s the gadfly image, the Socratic gadfly: refusing to accept any platitudes or accepted wisdom without examining it.” ~ Donna Dickenson

I think it used to be an enquiry into what’s true and how people should live; it’s distantly related to that still, but I’d say the distance is growing rather than narrowing.” ~ John Dunn

Philosophy is conceptual engineering. That means dealing with questions that are open to informed reasonable disagreement by providing new concepts that can be superseded in the future if more economic solutions can be found — but it’s a matter of rational agreement.” ~ Luciano Floridi

I’m afraid I have a very unhelpful answer to that, because it’s only a negative answer. It’s the answer that Friedrich Schlegel gave in his Athenaeum Fragments: philosophy is a way of trying to be a systematic spirit without having a system.” ~ Raymond Geuss

Philosophy is thinking as clearly as possible about the most fundamental concepts that reach through all the disciplines.” ~ Anthony Kenny

[A philosopher] is a moral entrepreneur. It’s a nice image. It’s somebody who creates new ways of evaluating things — what’s important, what’s worthwhile — that changes how an entire culture or an entire people understand those things.” ~ Brian Leiter

(A good editor, then, is also a philosopher — he or she, too, frames for an audience what matters in the world and why.)

I think that philosophy in the classical sense is the love of wisdom. So the question then is ‘What is wisdom?’ And I think wisdom is understanding what really matters in the world.” ~ Thomas Pogge

I’m hard pressed to say, but one thing that is certainly true is that ‘What is Philosophy?’ is itself a strikingly philosophical question.” ~ A. W. Moore

I can’t answer that directly. I will tell you why I became a philosopher. I became a philosopher because I wanted to be able to talk about many, many things, ideally with knowledge, but sometimes not quite the amount of knowledge that I would need if I were to be a specialist in them. It allows you to be many different things. And plurality and complexity are very, very important to me.” ~ Alexander Nehemas

A number of philosophers are particularly concerned with teasing out the difference between science and philosophy:

Philosophy is thinking hard about the most difficult problems that there are. And you might think scientists do that too, but there’s a certain kind of question whose difficulty can’t be resolved by getting more empirical evidence. It requires an untangling of presuppositions: figuring out that our thinking is being driven by ideas we didn’t even realize that we had. And that’s what philosophy is.” ~ David Papineau

I regard philosophy as a mode of enquiry rather than a particular set of subjects. I regard it as involving the kind of questions where your’e not trying to find out how your ideas latch on to the world, whether your ideas are true or not, in the way that science is doing, but more about how your ideas hang together. This means that philosophical questions will arise in a lot of subjects.” ~ Janet Radcliffe Richards

(Though, one might argue, some of the greatest scientists of all time, including Albert Einstein and Stephen Hawking to name but just two, were only able to develop their theories because they blended the empirical with the deeply conceptual.)

Philosophy is reflecting critically on the way things are. That includes reflecting critically on social and political and economic arrangements. It always intimates the possibility that things could be other than they are. And better..” ~ Michael Sandel

Well, I can tell you how philosophical problems arise in my view, which is where two common-sense notions push in different directions, and then philosophy gets started. And I suppose I also think that anything that claims to be philosophy which can’t be related back to a problem that arises in that way probably is empty.” ~ Jonathan Wolff

I think the Greek term has it exactly right; it’s a way of loving knowledge.” ~ Robert Rowland Smith

Philosophy Bites is excellent in its entirety, examining such diverse facets of philosophy as ethics, politics, metaphysics and the mind, aesthetics, religion and atheism, and the meaning of life.

* The complete selection of answers in Philosophy Bites features 44 male philosophers and 8 female ones — it seems, sadly, many women took, and perhaps continue to take, the words of that token old-order “eminent philosopher” at face value. What might Einstein say?