The aim of this post is to describe for the general reader some of the main features of contemporary analytic philosophy, with a focus on metaphysics. My hope is that, having taken 20 minutes to read this, people without the background will be much better equipped to read the Stanford Encyclopedia of Philosophy or even have a go at actual books and articles.
My plan will be to look at the ‘credo’ of a particular recent school of philosophers. I do so not because the views defended by that school are universally accepted by analytic philosophers, but because the credo happens to use much of the terminology, and say something about many of the debates, that you need to understand contemporary analytic philosophy. To see what analytic philosophers in general in fact believe, check out the philpapers survey. You will see that the consensus is that there is no consensus, and that moreover analytic philosophy goes beyond the debates introduced below.
The original document, written by the philosopher Daniel Nolan in 1996, can be found here. I thank him for letting me use it and for clearing something up for me, but want to explicitly note that any errors remaining — and I’m almost certain there are some, although I’m also pretty sure it’s mostly accurate — are my fault. Relatedly, in an article that attempts to cover so much, simplifications have to be made: this is most definitely a first word, and nothing should be taken as definitive statements of views. Rather, the hope is that it’s a quick way to get a zoomed out lay of the land.
I haven’t included further reading: a good place to start is always the SEP (I consulted a couple of articles while writing this), and if you want more ask in the comments.
The Canberra Plan Credo
The text of the credo is in italics, and my commentary in normal text. Key technical terms are bolded.
() We believe in a mind-independent, metaphysically real world
A good start! You might wonder … why does this need to be said? But that there exists a mind-independent world has, in one form or another, and to varying degrees, been denied. You might know of famous figures from the history of philosophy who said this, like Bishop Berkeley, for whom objects were ideas in the mind of God. And you might know of famous contemporaries in ‘continental’ philosophy who seem to deny the existence of an external world, like Jean Francois Lyotard who said, somewhat bafflingly, that the first Gulf War didn’t happen.
Most analytic metaphysicians go in for metaphysical realism. But it’s useful to note that not long ago, famous and renowned analytic philosophers defended anti-realism, and that’s what makes the statement not redundant.
(It’s not the easiest to describe in a short paragraph the arguments for anti-realism that were popular among analytic philosophers. Extremely roughly, one — associated with Michael Dummett — had it that understanding a language is a question of being able to tell whether its sentences were true or not. We understand ‘it’s raining’ because we have a way of working out whether it’s true on a given occasion of use: look outside, check the forecast, etc. But some sentences aren’t like that. We have no way of working out whether some sentences from the past are true. No way of telling whether ‘Shakespeare ate eggs on his ninth birthday’ is true. So, this line goes, such sentences (as well as their negations: ‘Shakespeare didn’t eat eggs on his ninth birthday’) are neither true nor false. But it’s surely a feature of a realist viewpoint that there’s a fact of the matter about Shakespeare’s birthday eating habits, and so this view of meaning is inconsistent with such a realist viewpoint and supports anti-realism.)
The point is, that anti-realism was not unheard of among analytic philosophers in the 20the century. It’s true, however, that it’s considerably less in vogue today. We are, for the most part, realists (although not necessarily realistic, as you’ll see shortly).
() and the *correspondence theory of truth.*
According to the correspondence theory of truth, true sentences or statements correspond to bits of reality. So, for example, it’s true that I ran this morning and so there is a bit of reality that corresponds to the sentence ‘Matt ran this morning’. It’s false that I swam this morning and so there is no bit of reality corresponding to ‘Matt swam this morning’. You might wonder why this gets its own line. Isn’t this just another way of getting at the idea of realism?
No. You can be a realist without liking a correspondence theory of truth, which for a long time was viewed as too metaphysically loaded. To see that, think about the question: what are the bits of reality like that make our sentences true?
It seems that, in our example, the bit must involve me. But it can’t just be me. Maybe the bit consisting just of me could be what ‘Matt exists’ corresponds to, but surely the bit for ‘Matt ran this morning’ must involve, somehow, running. Then maybe we could say this: the bit consists in the object, me, and the property of running, connected together.
But this is already to say quite a lot! After all, what are properties? If you were in a room containing solely an orange on a table, and you were asked how many entities there were in the room, you would say two — the orange and the table. You would not say (at least) four: the orange, the table, the orangeness of the orange, the squareness of the table (the roundness of the orange, the …).
It seems that we normal speakers and thinkers don’t recognise properties, and you if you were particularly concerned with doing justice to ordinary speakers, you might want to deny that properties really exist. And then it would be harder to defend the correspondence theory.
Things stray further from common sense when you consider more complicated truths. If I didn’t swim this morning, then ‘I didn’t swim’ is true. Then there’s a bit of reality it corresponds to. But what bit is that? There’s a sense in which at least we can gesture at the bit of reality corresponding to my running, but it doesn’t seem like any bit of reality corresponds to my not swimming. That, after all, is the point!
To capture things like negative truths it seems we’re going to have to have some very weird bits of reality, and that’s why, despite surface appearances, the correspondence theory of truth is a substantial commitment and involves one in thinking about the nature of reality quite a lot. The debate has moved on in the intervening years, and you’re likely also to hear about truthmakers, and — the current hot topic du jour in metaphysics — grounding, which are both ideas in the same ballpark.
() We believe in the reality of the past, and of the future,
and we are *four-dimensionalists (or at least three-plus-one dimensionalists) about spacetime.*
So what do you think about the first sentence here? Common sense or not? Certainly it seems like the future bit is less certain. After all, you might think, if it’s real, it’s out there, and its nature is determined already, which wouldn’t be great for those of us who think we have free will. If the future is real like the past, given the past is locked in and unchangeable, then the future is also locked in and unchangeable.
Last night, for example, I intended to work this morning. It turns out that I am in fact blogging. If the future exists, then the bit of reality consisting of me blogging already existed as a (to speak loosely) future fact. But then it seems I don’t have control over what I do in the future just as I don’t have control, now, over what happened in the past. I can’t change the past because it’s already there, and on this view, it seems the same applies to the future. Nevertheless, partly for reasons to do with contemporary scientific views about time (such as the relativity of simultaneity of special relativity) and partly for other reasons, many philosophers like the idea that the future exists on a par with the past.
I take the second sentence here to cash out in technical terms the first. In particular, as I understand it, four-dimensionalism is the view that time is another dimension alongside the spatial ones, on a par (or maybe not quite — per the parenthesis) with them (it also goes by the name eternalism, and is here opposed primarily — but definitely not exclusively — by presentism, which says that only the present exists). It goes along well with a view about the nature of objects according to which they too are four-dimensional. On this view (called perdurance theory), objects are extended through time somewhat like my body, for example, is extended through space. Similarly, on this view, just as I have spatial parts located at different locations in space, so I have temporal parts located at different locations in time: there’s a part of me that’s running located at 9am this morning, for example.
() We believe in *conceptual analysis, the a priori , and narrow content.*
I think the best way to understand these three views is as being about the nature of concepts or meanings. It’s reasonably common ground among philosophers to say that words and expressions have meaning or express a concept, which meaning/concept are also the objects of thought. These views then spell out some features of concepts. The first says that concepts are complex, structured entities, which structure gives rise to a certain sort of truth. The second tells us that the concept or meaning associated with some sentences is epistemically special, and the third tells us about two different ways concepts can be related to the world.
Conceptual analysis is understood differently by different people, but on one way of thinking about it it’s a view according to which the objects of thought have a certain structure which can be investigated and uncovered to yield knowledge. On this way of thinking, the goal of analysis is to say what the component parts of the concept are and how they hang together. A famous — and famously incorrect — analysis of the concept of knowledge would have it that knowledge is justified true belief. We can think of it then as composed of the concepts justification, truth, and belief. On this story, philosophy would be at least in part an ‘armchair’ discipline — you sit around and inspect concepts and try to find their structure, and in so doing learn new and non-obvious truths about the world.
Some concepts or meanings correspond to sentences — they are often called thoughts. The notion of the a priori concerns thoughts. It says that some thoughts can be known to be true independently of experience.
Most thoughts aren’t like that. The thought I’ve just thought that it’s raining, for example, can’t be known to be true independently of experience. I need to look outside the window to check. Such truths are called a posteriori.
Examples of a priori truths include the truth that all bachelors are unmarried, or that all physical objects have a colour, or that 2+2=4. In each case, it seems, merely grasping the thought lets us see that it’s true.
The idea of narrow content is best brought out by means of a — famous — example (from Hilary Putnam). Water in our world is the chemical element H2O. Imagine a world in every other respect like ours but in which the potable clear liquid that is in rivers and so in is the chemical element XYZ. That it’s like our world in every respect means that it contains people who speak English and call XYZ ‘water’ — indeed, it contains someone identical to me except he is 90% XYZ. Imagine those people before the discovery of organic chemistry, so they don’t know it’s XYZ, and imagine us at the same time (so we don’t know it’s H2O) . I and my twin say ‘Water is delicious’. Do we mean the same thing?
Well, on the one hand exactly the same thoughts and images and come to mind; we associate the same dictionary entry with the world, and we behave with regards to what we call ‘water’ the same way. So it seems a good case can be made for saying yes, we mean the same thing. On that view, meanings would be in a sense internal to the speaker: it doesn’t matter what’s actually out there (which differs for me and my twin), but just instead how we think of it, how we behave with regards to it, and so on. Narrow content is this type of internal content or meaning that my twin and I share as a result of being duplicates. This example shows two people can share narrow content even if the thing in the world their thoughts are about are different.
But you might doubt this. Surely, you might think, meaning tracks how the world actually is — our thoughts are about a particular chunk of reality, and if that chunk is different, our thoughts are different. This is the view known as externalism about content, and it’s one of the most influential views of the 20th century (if you take just one thing away from this article, externalism would probably be most useful: related terms you might want to research and know are descriptivism and Fregeanism and direct reference theory and Millianism. Roughly, the firs two go with narrow content and the second two with wide content.)
Externalism goes with what is called wide content, which is the sort of mental content that is sensitive to environmental conditions and according to which concepts or meaning reach out to the world and have their identity determined by it. My twin and I have different wide contents for ‘water’. My wide content for ‘water’ is simply H2O itself, while my twin’s is XYZ. It sounds a bit weird to say that a substance is a type of content, but that is indeed what people say.
Narrow content, on the other hand, is that content that we share. A lot of ink is spilled as to whether wide or narrow content is the important one — whether it best accounts for what our words mean, or how belief spurs action — but one approach is just to say that they are both important and to say that we have both narrow and wide content (indeed, as Nolan notes in his comments, the tendency to favour a two-dimensional theory of meaning is a notable feature of the Canberra planners. Two-dimensional semantics is the term, although it’s not easy for the beginner).
() *Ramsification over platitudes leads to the systematisation of theory, and thereby enables identification of the best deservers for theoretical terms.*
I think this is perhaps less crucial to know (admittedly, I say this mainly because I managed to go about ten years in philosophy resolutely not bothering to learn what ‘Ramsification’ meant), so I’ll be somewhat quick. Say we have a theory of some bit of the world. It consists of words standing for things that we make into sentences that are true or false. Most of these words will be good, familiar words. Say we want to give a theory of human beings. We’ll talk about stomachs and smiling and protein and feet. But we’ll also talk about slightly more hard to deal with words, words for things that we can’t see, like pain or joy or just consciousness.
Famously, these sorts of words lead to hard problems. What is, after all, pain or consciousness? How do we fit pain into our theory of the world, alongside feet and smiling? The Ramsification idea is that we take a bunch of things we uncontroversially know about pain, for example that pain is caused by injury to the body by some stimulus and pain causes people to say ‘ow’. We can know these things even if we’re confused by what pain actually is in a deep metaphysical sense.
We can use these uncontroversial things to get some knowledge as to what pain is. The basic idea is that we can replace the controversial term (‘pain’) in our list of obvious truths about pain with gaps, like so:
__ is caused by injury and __ causes people to say ‘ow’
And we can then do what is called (existentially) binding the gaps, where we quantify over the gappy sentence yielding (don’t worry about the unexplained jargon in this sentence too much; I explain some of it in my philosophy of language piece linked below):
(*) There is some thing such that it is caused by injury and it causes people to say ‘ow’.
There’s something neat about this. We started with a theory that involved something weird we didn’t understand. We then converted that theory to another theory, specified above, that doesn’t involve mentioning anything weird — we generalized to get rid of the weirdness. Now our theory is nice and respectable, containing only nice scientifically understandable words and ideas about causation and injury and speech.
Now, if we assume our theory is true, then this sentence is uncontroversially true, and has no weird unclear terms in it. But if it’s true, then there’s some thing that has those properties — something that, to use some jargon, satisfies the existential quantification (the ‘there is some thing’ sentence).
We can then say that that’s what ‘pain’ stands for: it stands for whatever the object is that makes (*) true. In that way, we can parlay our knowledge of uncontroversial truths and unweird entities into a sort of knowledge about the weirder things, by saying that the weirder thing is just whatever it is plays a certain role in our overall theory. This, more or less, is Ramsification, and — as my example might have suggested — was used as a tool in the philosophy of mind (and elsewhere) to help understand the hard to understand.
() We are *materialists and functionalists about the mind.*
Materialism — although it might mean slightly different things in different mouths — is the idea that there is (perhaps at some deep down level, whatever that means) just one type of thing in the world, physical things. About the mind in particular this means that the mind is not, as other philosophical and religious traditions would have it, a separate type of entity other than, say, the body associated with it. Materialism about the mind is thus a rejection of dualism, according to which there are two types of things in the world, minds and bodies. Functionalism is the idea is that mental states are defined by the role that they play in a person’s behaviour. As we just say, pain, for example, can be thought of as that state, whatever it is, that is caused by injury and causes ‘ows’, in general the functionalist idea is that we don’t have to know how in particular a given state is realized — that is incidental — we just have to know its causal patterns. A consequence of being a functionalist about mental states is that we allow other creatures and even non-organic entities to have mental states, provided there is something that plays the same causal role (injury detection and warning) as pain does in us.
()We reject spooks and *epiphenomena of all sorts.*
Spooks are the non-physical things, the sort we might be worried about fitting into a respectable scientific theory. Epiphenomena more particularly are things which have no causal effect. On one view of the mind, consciousness would be an epiphenomena. In general, fitting epiphenomena into a nice scientifically respectable theory is tricky, and the Canberra planners want none of it.
()We are Humean about value, but not about causation.
Humeanism about value (this is the thing I’m least sure about in this essay, so reader beware) is the idea that value isn’t something inherent in an object, but something that depends on human actions, and in particular on human’s valuing it. We value good music not because of some inherent, kind of weird, property of its being valuable, but because — and kind of circularly sounding — we adopt certain attitudes to it, the attitude of valuing. Valuing is a state of ours we bring to the object, not a state of the object that impinges on us.
Hume’s famous theory of causation, which remained popular in one form or another in a good chunk of the 20th century, has it that for a given event of type a to cause a given event of type b is for it to generally be the case that b events follow a events. This has some advantages: in a sense, it deflates something kind of weird seeming. When I eat something, I feel sated. These are two different events, as different, you might think, as me eating and it raining in Brazil. But they have this weird close connection: pretty much always, whenever I eat, I feel sated. What is this weird close connection, that knits together to events in a way to most events aren’t knitted? The Humean’s reassuring response is, pretty much, ‘nothing’. It’s just a fact that some events always follow others, but that’s all there is to it.
However, that’s not very satisfying, because it’s going to require some fancy footwork to exclude bad cases. Whenever the sun rises, the sun (a bit later) sets. But the sun’s rising doesn’t cause its setting. In the last bit of the twentieth century, when people became less uncomfortable with confronting the weird bits of reality, a flurry of theorizing took place about the metaphysics of causation according to which it was some real metaphysically robust thing, and today that would be the general consensus (although the details, as ever, are much debated).
()We believe in the reality of *properties and *relations
(though we are agnostic about whether they are *universals,* tropes* or special sets).*
Properties are ways things can be, ways like being green, while relations are the generalization of properties to ways of being that involve more than one object: being taller than, for example, is a relation. As suggested above, it doesn’t seem like a commonsensical view that there are properties, and trying to say something about their nature is even more difficult, but if you want to do metaphysical theorizing, these are issues you need to deal with, and both have and do receive a lot of attention. Nowdays most are realists about them, as opposed to nominalists, who don’t think they really exist.
But if they do really exist, what are they? The next sentence lays out some of the seminal options. The key feature of a theory of universals is that for an object for it to be a certain way is for it to possess a certain universal, and, since two objects can be the same way, more than one object can possess a given universal. When one beholds, for example, a cup’s being green, the thing one is seeing (maybe) is a cup being related to the property green, while if you turn your head and see the grass’s being green, you see the grass being related to the very same object, the property green. One possible way to gloss this is to say that universals are objects located at more than one place in space. A trope, sometimes called a particular quality instance, is, unlike universals, not shared. In the situation just described, there would be one green trope associated with the cup and another with the grass. Tropes are particular objects, like, for example, human beings, but unlike human beings, they do not possess qualities, but are qualities. Tropes go well with a bundle theory of objects, according to which objects are just collections of tropes. According to the third view, properties are just sets of objects. The property blue would be the set of blue things. There needs to be something more to it than it, because for any objects, there is a set consisting of those objects, but it’s not the case that for any objects, there’s a property they share (or, at least, it does some violence to our intuitive notion of property to say this.) And that, I take it, is why they have to be special.
() We believe in *unrestricted mereological composition, and believe in the existence of sets*
The fourteen syllable ‘unrestricted mereological composition’ is perhaps as hard to understand as it is to parse. Let’s break it down. ‘Mereological’ means to do with the theory of parts and wholes. Composition is how parts come together to form unified objects. Unrestricted mereological composition is a particular view about how parts come together to form wholes according to which, for any objects, there is an object which has they and only they as parts.
This is super weird. For the friend of UMC, the Eiffel tower, Jonathan Franzen, and Ume the dog are all (and only) parts of some object. This is a very weird object which, of course, none of us would be inclined to believe in, but there’s a certain logical neatness to it — since we think sometimes objects compose to form another object (as the parts of my body compose my body) the thought goes that the simplest solution is to say that they always do. Although it sounds ridiculous, here’s a challenge: fill in this sentence in a way that is motivated. Objects, x1,x2,…,xn compose an object w if and only if ___ where you can and should mention x1,x2,…,xn in the blank bit. It’s not so easy! Belief in sets is pretty common among philosophers interested in sets, although there is at least one interesting opposing view (David Lewis, who put forward a view for how to do set theory using the resources of mereology).
() We believe in *possible worlds (though we admit puzzlement about their nature).*
This is another important one. You won’t go far in contemporary philosophy before encountering possible worlds talk. It was introduced by Saul Kripke in the ‘50s as a way of formalizing what is called modal logic, an important variety of which is the logic of possibility and necessity. What is it to say that 2+2 is necessarily 4? On this thought, it’s to say that there are these things, possible worlds, which are ways things the world could be and for something to be necessarily true is for it to be true relative to all possible worlds. For it to be possibly true is for it to be true at at least one of these things. Just as we typically understand truth as relative to a world (to say that it’s not raining is true is really to say it’s not raining (here) in this world) we can and should also consider truth relative to ways the world can be other than it actually is.
You might wonder what the fuss is, but we have very good understanding of the logic of expressions like ‘all these x’ and ‘at least one of these x’, and we can use that understanding (replacing ‘x’ with ‘worlds) to develop formal mathematical theories of modal logic, as Kripke famously did.
But equally important is that you can do a lot of philosophy with possibility and necessity. Here is but one example. Remember we said that one view of properties is that they are just sets — so, the property of having a heart is just the set of things that have a heart. But all and only those objects that have a heart have a kidney (at least for the sake of this example, I don’t know about the biological accuracy of this). That means that the property of having a kidney is the same set of objects as the set of objects having a heart — the behearted, bekidneyed ones. That means the two properties are the same — but surely they aren’t.
If we can use the resources of possibility and necessity, we can avoid this problem. We can say that two properties are the same provided it’s necessary that their associated sets have the same members. A property isn’t just one set, but is rather a bunch of different sets, one different one for each possible world. Even if, as a matter of fact, all hearted creatures are kidneyed creatures, this obviously isn’t a necessary truth, and so the sets the two properties correspond to will differ at some possible worlds, allowing us to tell them apart.
But now we’ve moved from logic and language (the modal logic stuff) to metaphysics. We want to say what properties are, and for that to be in good standing, it seems we are committed to saying both that possible worlds are something, and to saying what they are. And so, given the role they can play (and this is just one example) philosophers felt led to take possible worlds seriously. And that’s what the credo is saying here.
*() We believe in morals, and colours, and all manner of *“secondary qualities”.
This is another statement of the nice robust realism that typifies much contemporary work. Earlier in the 20th century, anti-realism about morals, for example, was in vogue. People thought that properties like being wrong didn’t really exist, and that to say, for example, ‘murder is wrong’ was just to say that you weren’t a big fan of murder — to express your disapproval of it. Nowadays, I think, to a large extent philosophers tend to be moral realists. Secondary qualities are ways things are that in some sense depend on the properties of an observer — colour is a paradigm, but other sensory properties should be included here too. I think the reason it’s being mentioned is because it was thought such things are harder to square with a materialist view of the world, or in some sense less real because not entirely mind-independent, and plenty of work in twentieth century philosophy has been concerned to push back against this.
() We are *consequentialists, but of all shades, and with a variety of meta-ethical justifications.*
Continuing with the discussion of morality, consequentialism is the idea that the goodness of an action is determined by its consequences. Utilitarianism, for example, as the most famous consequentialist theory, is concerned with those actions which produce the most happiness or utility or pleasure, where that is found by totting up how much happiness (or etc.) the action produces and taking the amount of unhappiness it produces away from it. There are a ton of different consequentialist theories (some think, for example, that it’s rules rather than particular actions that we should judge based on — do actions which are in accordance with maximising rules). And one can be a consequentialist for different reasons. Opposing consequentialist theories are deontological theories, which is the idea that an idea is right provided it is done in accordance with the rules of right behaviour, regardless if it has less than the best or even bad consequences some times.
() We believe in the substantial correctness of the doctrines of *David Lewis about most things (except the nature of possible worlds).*
You might not think you know much about David Lewis, but if you’ve been following along you do know some. He is an extraordinarily influential figure who set the terms of many of the debates, including some of those mentioned above, and I would have to imagine that ranking any hundreds or thousands of years hence would put him in the top ten philosophers of all time. (On the topic of ranking: a very important feature of analytic philosophy is that we are obsessed with rankings. Ranking is probably the third most important concept necessary to understand contemporary philosophy, alongside externalism and possible worlds. I’m — only just — joking.)
It’s thus kind of unfortunate that the thing for which he is most famous is the rather implausible view of modal realism, a view of possible worlds according to which all possible worlds are concrete objects just like ours. The only thing that differentiates our world from other possible worlds is that this world is ours — the one we’re located at (the other possible worlds are spatio-temporally separate from ours — we can’t travel to them). He believed this wacky doctrine in part for the reason mentioned above — having possible worlds around really makes metaphysical theorizing go smoothly.
() We respect the opinions of the folk, and are naturalists, with great respect for the findings of science (suitably interpreted).
You might question this first bit in light of, among other things, the talk of mereological universalism! But nevertheless this is mostly accurate, I think, of how contemporary philosophers view themselves. If at any point reading this you’ve thought a view must be wrong because it conflicts with something from a natural science, you probably — only probably — want to think again, because views ignorant of relevant science will typically pretty quickly get tossed aside (although sometimes this process might take a while before we realize the science in question is relevant).
()We look for inter-theoretic reductions,
And the *supervenience of all on the microphysical*,
And this final sentence indicates a desire to reduce theories belonging to a given level of abstraction to ‘lower’ theories. To know how, for example, to reduce one’s theories of chemistry or psychology, say, to physics ending with the thought that reality is at bottom what fundamental physics tells us, and changes at the higher levels of reality (in psychology, say) are always the result of (**supervene on) **changes at the lowest microphysical level.
So ends our quick tour of contemporary philosophy. Any of these sentences could have been the topic of its own article (book, research program, lifetime, …) and so this has been necessarily quick and incomplete. But I hope you now have a better grasp of the often forbiddingly technical jargon of contemporary philosophy as well as a broad sense of how (some) contemporary philosophers view the world and the aim of philosophy. In particular, hopefully you can see that much contemporary philosophy is realist in spirit, with an interest in exploring the structure of reality in a way guided by science and commonsense but never afraid to diverge from it if that is where argument leads.
Some other introductory articles about philosophy: