“Yes; but, don’t you see, he hasn’t. Marryatt’s a very good chap, and he thinks all the doctrines he preaches are more probable than not, but his religion doesn’t sweep him off his feet: the man who denies it doesn’t seem to him something less than human. That was another reason against your theory. Psychologically, Marryatt hasn’t got the apparatus to do what you thought he did. Morally, he hasn’t got the motive to act as you thought he did.” “Well, I seem to have made a pretty good ass of myself all round. I wonder if anybody in the world has ever been so led astray by a theory?” “Anybody ever? Why, my dear Reeves, you’re in exactly the same position there as about three-quarters of the modern world: they are all led astray by theories. Only you were at least led astray by your own theory, not by one you’d borrowed at second-hand.” “What, you mean scientific theories in medicine and so on? Taking the doctors’ word for it that it’s a good thing to be vaccinated, and that kind of thing?” “No, hang it all, it would be unfair to complain of that. It’s better for the doctors to have a false theory than no theory at all. They make mistakes, but sooner or later they find out they were wrong. It’s bad luck on all the people who happen to have died from getting the wrong treatment, but still, we did our best. No, I don’t mean the guess-work by which we live from day to day, and which is necessary to living: I mean the theories learned people propound to us about the past, about the meaning of human history.” “Darwin, and all that?” “No, not exactly. I grant you that does illustrate my point. Evolution is only a theory, and the relationship of the monkey to the man not even a plausible theory; and yet they have gone on so long without being positively disproved that everybody talks as if they were proved. The scientist still treats evolution as a theory, the educationalist treats it as a fact. There’s a curious sort of statute of limitations in the learned world which makes it impossible to call a man a liar if he has gone on lying successfully for fifty years. But, after all, there’s something to be said for the Evolutionists. They did set out to explain a real problem, why there should be more than one kind of thing in the world; and they don’t even profess to have explained it. The theorizers I mean are people who create problems where none exist—as you did, Reeves, when you insisted on regarding it as an open question who murdered Brotherhood. They are people who trust circumstantial evidence in the face of all common human probability, as you did, Reeves, when you wanted to convict a chump like Marryatt of murder on the strength of a chain of silly coincidences.” “All this comes out of your diary, I suppose?”