TAMARUS: But ideas are like money. There must be an accepted coin which circulates. Concepts which are used for communication are justified by success.
ANNANDINE: That's near to saying that a story is true if enough people believe it.
TAMARUS: Of course I don't mean that. If I use an analogy or invent a concept part of what must be tested when the success is tested is whether by this means I can draw attention to real things in the world. Any concept can be misused. Any sentence can state a falsehood. But words themselves don't tell lies. A concept may have limitations but these won't mislead if I expose them in my use of it.
ANNANDINE: Yes, that's the grand style of lying. Put down your best half truth and call it a lie, but let it stand all the same. It will survive when your qualifications have been forgotten, even by yourself.
TAMARUS: But life has to be lived, and to be lived it has to be understood. This process is called civilization. What you say goes against our very nature. We are rational animals in the sense of theory-making animals.
ANNANDINE: When you've been most warmly involved in life, when you've most felt yourself to be a man, has a theory ever helped you? Is it not then that you meet with things themselves naked? Has a theory helped you when you were in doubt about what to do? Are not these very simple moments when theories are shilly-shallying? And don't you realize this very clearly at such moments?
TAMARUS: My answer is twofold. Firstly that I may not reflect upon theories, but I may be expressing one all the same. Secondly that there are theories abroad in the world, political ones for instance, and so we have to deal with them in our thoughts, and that at moments of decision too.
ANNANDINE: If by expressing a theory you mean that someone else could make a theory of what you do, of course that is true and uninteresting. What I speak of is the real decision as we experience it; and here the movement away from theory and generality is the movement towards truth. All theorizing is flight. We must be ruled by the situation itself and this is unutterably particular. Indeed it is something to which we can never get close enough, however hard we may try as it were to crawl under the net.
TAMARUS: That may be. But what about my other point?
ANNANDINE: It is true that theories may often be part of a situation that one has to contend with. But then all sorts of obvious lies and fantasies may be a part of such a situation; and you would say that one must be good at detecting and shunning lies, and not that one must be good at lying.
TAMARUS: So you would cut all speech, except the very simplest out of human life altogether. To do this would be to take away our very means of understanding ourselves and making life endurable.
ANNANDINE: Why should life be made endurable? I know that nothing consoles and nothing justifies except a story – but that doesn't stop all stories from being lies. Only the greatest men can speak and still be truthful. Any artist knows this obscurely; he knows that a theory is death, and that all expression is weighted with theory. Only the strongest can rise against that weight. For most of us, for almost all of us, truth can be attained, if at all, only in silence.

Iris Murdoch, Under The Net (Penguin Books, 1960) pp. 80-81