“And it wasn’t merely the general setting, it was the details. How could Marryatt know that the train would be held up by signals just there? How could he tell that Brotherhood would get into the part of the train which hadn’t got a corridor, and that he would get into an empty carriage? What would he have been able to do, if Brotherhood had happened to come back as he always did—did, in fact, come back on Tuesday—in a crowded train like the 3.47? How could he be certain that nobody had seen Brotherhood get into the three o’clock? That nobody had noticed him at Weighford? Alternately, don’t you see, you make your man take the most superhumanly cunning precautions, and then trust to blind chance. But those are all objections of detail. I didn’t mention them because, as I say, you’d have found some sort of answer for each. My real objection was much deeper.” “Well, why didn’t you tell me about _that_?” “Because you wouldn’t have begun to understand it. It’s concerned, you see, with people, not with things. It’s simply that Davenant is the kind of person who would kill a man, and Marryatt isn’t.” “You mean because Marryatt’s a parson? But, dash it all, Davenant goes to church.” “Davenant goes to church, but he isn’t the sort of person who goes to church. With Protestants, I mean, it’s ordinarily safe to assume that if people do go to church they are of a church-going type; they belong to the ‘unco’ guid.’ That isn’t a safe assumption to make about Catholics; they seem to go to church whether they’re ‘unco’ guid’ or not. I don’t mean that Davenant’s a stage villain, but he’s just an ordinary sort of person, and he’s got red blood in him, whereas Marryatt hasn’t—I hope it’s not unkind to say so. He wouldn’t kill a man; you may almost say he couldn’t.” “Couldn’t morally, you mean, or couldn’t physically?” “I don’t mean either. ‘Couldn’t psychically’ would be nearer the mark. For one thing, Davenant’s fought in the war, and killed people, I expect—he was a bombing officer, wasn’t he? Well, you know, I think to most people that makes an enormous difference. I suppose that’s why there’s generally a ‘crime-wave’ after wars—part of the reason, anyhow. People have got accustomed to killing, and it isn’t easy to murder people till you’ve done that.” “And Marryatt, you mean, really couldn’t kill a man?” “Physically he could—he’s rather strong. Morally he could—morally any of us could do anything. Or so they taught us when we were small. But there’s a third difficulty you’ve got to get over, if you want to murder people; a sort of nervous repugnance to the job. I don’t say that if Marryatt went to the bad, he mightn’t screw himself up to the point of shoving poison into somebody’s tea. But he couldn’t kill a man with his hands.” “I know; it doesn’t sound probable. And yet, I suppose a person with a fixed idea isn’t much different from a madman, is he? And my argument was that Marryatt had a sort of fixed idea about religion.”