Is being unreasonable reasonable? Certainly if you can only be happy with some amount of unreasonable beliefs, and you value happiness to any degree (and really, who doesn't?).
The Faith Machine deals with why having faith might be reasonable, even when you are quite conscious of its unreasonable nature. It deals with it on two levels faith vs pessimism regarding the human conditions, and in the everyday - faith in relationships.
Its protagonists are a couple, one a preachy, academic charity worker, the other a pragmatic ad-man, who has turned his back on writing. Their relationship fails as she demands that he considers the moral consequences of his work. He replies that this is a slightly ridiculous request, as we're just:
"fucking animals in the fucking dark, eating each other, fucking eating, killing, destroying each other"
Which is the kind of thing you say when you're an upset person today. It immediately reminded me of a similar sentiment in similar words, but the words of a 19th century aesthete, Mr Matthew Arnold:
"we are here as on a darkling plain Swept with confused alarms of struggle and flight Where ignorant armies clash by night"
Matthew Arnold, Dover Beach
Lots of the language reminds me of the Victorian writers who were on the front-line of science's systematic demolition of the faith of most thinking people. Lyle's discovery that the earth was of a rather earlier vintage than the bible suggested. Darwin's slow burning suggestion that "fucking eating, killing, destroying" was the rather unpleasant "immortal hand or eye" that framed the tiger's fearful symmetry. Carlyle asserted with his whole being that man was not "simple stomach" - a being of appetite - that the utilitarians saw us as "mere atoms" (Tom: "fucking appetite that's all", "fucking atoms").
It's unfinished business. Why do we have faith in anything? I'm totally convinced that we are just "fucking appetite", randomly emerged on a big lump of rock, in a universe that could easily disintegrate the whole earth via a super-nova. I also know I'm a big wuss, more liable to cry during films than my girl friend, totally awestruck by pictures of the universe, or the scale of our planets. What I think this play states so well is that we are meaning seeking creatures, and it seems to be provoked by a feeling that militant atheists are out to deny that part of us.
Personally I'm quite happy to find meaning, beauty and reassurance in poetry and literature, including religious literature, without needing to believe it represents something real. I don't want to have to pretend that the universe has some meaning, because it'd keep reminding me how false that was via worms in children's eyes in Africa, or tsunami, or X-Factor.
What I do feel is that we have preferences, and that they at base need little justification. When Sarah attacks Tom for working with a pharma company that kills children, she does it because it upsets her. She might frame it rationally because God said it was naughty, or because of Kant's categorical imperative, but at base she's post-rationalising what she feels. So I'd say for people who want to hang about with Sarah, it's pretty important they share similar preferences, or there'll be friction.
Secondly I think our preferences can be illustrated, exercised, questioned and valorised by metaphor and the arts, in a way that they aren't by pure fact. When X in the play justifies his 47 year career in the church in his love for a "good fucking metaphor", I understand. Metaphour is why:
"Judgements are like watches none go just alike, yet each prefers his own"
is going to inspire people 1,000 years hence, and expositions of how peoples' opinions are subjective are going to sit in textbooks unquoted and unremembered. Metaphour brings our preferences into the light, gives us joy when we observe how they reinforce them.