He paused to light a cigarette before he continued.
“In real life,” he went on, “there isn’t any of this kind of simplification. You get a mass of stuff thrown at your head in the way of evidence; and in the end nine-tenths of it usually turns out to be completely irrelevant. You’ve got to sift the grain from the chaff yourself, with no author to do the rough work for you. Do you remember the Map-game?”
Wendover shook his head.
“I don’t recognise it from the title.”
“You must have played it sometime or other when you were a kid,” Sir Clinton continued. “One player chooses a name on a map; the other player’s got to find out which name it is. He can ask any questions he likes, provided that the first player can answer them by a plain ‘Yes’ or a ‘No.’ Now that game is something like detective work, though the problem’s much easier to solve. Curiously enough, the really clever player doesn’t choose a name in tiny type—only the beginner does that. The expert picks out some name like France, or Germany, or Czecho-Slovakia—something that stretches half-way across the map. Then when the opponent asks: ‘Is it on this half of the map?’ the expert answers ‘No,’ quite truthfully; and the beginner at once assumes that it must be in the other half and proceeds accordingly, quite forgetting that it may be on both halves simultaneously. That’s the kind of thing that may turn up in criminal-hunting. The fellow you’re after may be—in fact he generally is—playing two parts simultaneously. He’s not only a criminal; he’s a normal member of society as well—at least in murder cases he usually is. He stretches over both halves of the map, you see? And if you insist on looking at one half only, you miss him completely.”
“That’s a long suit of talk you had in your hand,” Wendover commented. “You seem very flush of information on some points.”
Sir Clinton laughed, admitting the hit.
“You asked for a lecture, and now it seems you don’t care for it when you get it. Well, try your hand yourself. Let’s hear what you’ve made of the case. I’m not afraid of prejudice now.”
Wendover glanced at his friend with some suspicion; but he seemed reassured by what he saw. Sir Clinton appeared to be quite anxious to hear his ideas.
“If you’re not pulling my leg, I don’t mind,” he said. “I’ve taken in most of what you said, and that limits things down a good deal. I’ll take the possibles, one by one, and consider them. The bother is that it’s difficult to find any one person who will fit into your three classes—I mean someone who had an opportunity, the method, and a motive strong enough.”