第8页 / 共657页

I could not help laughing at the ease with which he explained his

process of deduction. "When I hear you give your reasons," I

remarked, "the thing always appears to me to be so ridiculously

simple that I could easily do it myself, though at each

successive instance of your reasoning I am baffled until you

explain your process. And yet I believe that my eyes are as good

as yours."

"Quite so," he answered, lighting a cigarette, and throwing

himself down into an armchair. "You see, but you do not observe.

The distinction is clear. For example, you have frequently seen

the steps which lead up from the hall to this room."

"Frequently."

"How often?"

"Well, some hundreds of times."

"Then how many are there?"

"How many? I don't know."