10 September 1997
Thank you for your letter of 4 September, and your notes for unit one of The Possible World Machine, on 'possible worlds'.
It's worth seeing if you can get Miller and Smith's Thought Probes on inter-library loan. However, the book is not needed for the course: it's listed because it represents the nearest thing to what I am doing in The Possible World Machine.
Any introductory book which covers the central areas of philosophical inquiry would be a useful accompaniment to the course: just check the chapter headings and index. It isn't necessary to look up every book mentioned in the course units, though there's no harm in doing so, if a book catches your interest!
Of the books you mention, Sartre's novel Nausea will be useful when we come to the question of the basis for morals and the problem of freedom of the will. Plato's Phaedo and Symposium are both literary masterpieces and inspiring to read, though the latter is more light weight in terms of philosophical content.
Now to your notes:
1. Worlds 'governed by rules or concepts that are utterly unknown and unknowable to us' make an interesting category. But how do you know that such a description does not apply to our actual world? Kant, in the Critique of Pure Reason, talks of space and time as 'a priori forms of apperception', raising the possibility that there might be beings who perceive the same world — the same 'noumenal' reality — but in a totally different and (for us) inconceivable way. Recently, the philosopher Thomas Nagel (in his excellent book The View from Nowhere OUP 1986) has put forward quite a powerful argument for the possibility that there might be concepts which are inconceivable by human beings. One suggested example is the set of concepts needed to comprehend the relation between the mental and the physical.
2. There's every reason to speculate about possible worlds. Consider a court deciding whether a motorist caused the death of a pedestrian by his reckless driving. Or a scientist turning the dials on an experimental set-up. Or a historian investigating the conditions that led to the rise of the Nazis. Counter-factual statements such as 'If X had happened Y would have happened' or 'If W hadn't happened Z wouldn't have happened' are not just pointless speculations but necessary for understanding what takes place in the actual world.
3. In terms of the dialectic of scepticism, the sceptic is not in the least interested in proving that 'we' are dreaming. The whole point of scepticism is to deny the right to knowledge where there is no conclusive proof! The fact that I cannot absolutely rule out the possibility that I am dreaming that I am writing this letter (or the possibility that I am a brain in a jar in an aien scientist's laboratory) shows — according to the sceptic — that my so-called 'knowledge' of an external world fails to measure up to the definition of knowledge (More anon!)
4. We have to distinguish 'worlds that might have been' from 'worlds that there might be'. The possible distant past or future of our actual world are matters for speculation, just as worlds that might exist somewhere else in the actual universe. In this second sense, a 'possible world' is possible insofar as our present knowledge doesn't rule out its actual existence.
5. Another interesting category. At least some 'paranormal' phenomena (such as table-tapping spirits, or the ability to foresee the future) might be rejected on the grounds that the very idea is logically incoherent: the worlds they describe are 'impossible'. (Of course, we have to be careful, in view of 1., not to rely on arguments based merely on our ignorance, or the fact that we find certain notions 'inconceivable'.) Ideas that seem plausible when first described can turn out, on closer scrutiny, to involve a hidden contradiction or absurdity: that is one of the main points of the philosophical 'thought experiment'.
6. If this is not a point about knowledge and scepticism, then one might understand the 'worlds of our dreams' in a visionary sense. The function of such purposeful dreaming is to enlarge our imaginations, or make us see things differently. — Not unlike a definition of philosophy.
7. I totally agree here. The short stories in this programme represent my own first 'serious' attempt at writing fiction. I suspect that the capacity to create fictional worlds is closely tied with the human biological function of dreaming. One thing that puzzles me, though, is why are human beings interested in fictional worlds? Why do we find novels, plays, films, gripping? (A question Colin Radford investigates using the example of Anna Karenina in his book Driving to California (Edinburgh): it occurs to me that this book would be the closest in spirit to The Possible World Machine in its use of stories and dialogues.)
8. Some of the best science fiction does go deeply into philosophical issues. Philip K. Dick is very much a philosophers' favourite. Another author who uses science fiction to raise serious moral and social issues is Ursula LeGuinn. Robert Zelzany is another good example of a philosopher's science fiction writer.
9. Perhaps the most interesting category of all. When does false perception (e.g. successful propaganda, prejudice) become the literal truth? If Neil Hamilton is innocent then he is innocent, even if the whole world thinks he is guilty. But other cases are not so clear-cut. If amongst a 'primitive' peoples certain magic rites are seen as being efficatious, then — arguably — the repercussions of that belief are so wide spread as literally to 'change' reality. If I believe that someone has cast a magic spell on me, that is as good as actually having a magic spell cast on me. — There is an interesting book of papers, Rationality edited by Martin Hollis (Blackwell) which discusses these issues.
— Lot's to think about here. Do feel free to 'recycle' thoughts!
The idea that metaphysics deals with the 'unprovable' is a legacy of positivism: the idea that as science progresses, the area for 'metaphysical speculation' is progressively diminished. That is not my understanding of metaphysics, however. In philosophy, arguments are based on reason on logic, not appeals to experience and experiment. In these terms, I believe certain metaphysical propositions are provable — 'dialectically'. But that remains a controversial claim...