What is it about paradoxes? Perhaps they are best described as the intellectual equivalent of an itch that won't go away. Many of them are ancient, they usually can be stated in a sentence or two, and yet they can torment philosophers for centuries. Take the famous Liar Paradox.
Discovered by Epimenides in the 6th century BC, it is stated in a few words: someone says "What I am now saying is false." Well, if his statement is true, it is false, but if it is false, it is true. So it is true and false. But how can that be?
Some 2,500 years later philosophers are still obsessed by it.
There are various proposed solutions on offer, new proposals crop up every so often, and so do new sub-species of the paradox itself. Many articles and even whole books are still written about it, and there is no clear consensus on what the solution should be. This is some cause for discouragement but, on the other hand, one of the great things about paradoxes is the light they shed on all areas of philosophy. It is by beavering away at solutions that philosophers have illuminated the workings of language, logic, knowledge and the mind.
Paradoxes are an insidious occupational hazard, as Gottlob Frege discovered to his dismay when Bertrand Russell informed him of the paradox (now called Russell's Paradox, needless to say) that undermined Frege's innovative and monumental system of logic.
Some philosophers (maybe out of dismay at watching others trying to solve them) have concluded that paradoxes are the sort of thing we just have to live with. Others joyfully embrace paradoxes, as though their existence proved that life itself is full of bliss-inducing contradiction and plain weirdness. Nevertheless, the philosopher's job is to get at the truth, and the fact is that paradoxes have to be solved if truth is to be got at. For they defy logic and common sense, they eat away at coherent thought and consistent reasoning, and, anyway, trying to solve them is just plain fun.
Hence the growing number of books on paradox that are entering the literature. Michael Clark's new compendium of paradoxes is the latest and probably the best of its type. The alphabetical listing makes reference and cross-reference easy. Each entry begins with a brief statement of the paradox, followed by a more extended discussion of a few pages, which includes the main solutions on offer. The entry ends with further reading.
Technicality is avoided where possible, and the language is kept clear, concise and engaging.
Self-contained courses in paradox are not usually taught as part of a philosophy degree. There is good reason for thinking they should be, and this book would make the ideal text for just such a course.
David S. Oderberg is professor of philosophy, University of Reading.
Paradoxes from A to Z
Author - Michael Clark
Publisher - Routledge
Pages - 218
Price - £45.00 and £9.99
ISBN - 0 415 22808 5 and 22809 3