P. G. Wodehouse 
My Man Jeeves [EPUB ebook] 

Jeeves—my man, you know—is really a most extraordinary chap. So capable. Honestly, I shouldn't know what to do without him. On broader lines he's like those chappies who sit peering sadly over the marble battlements at the Pennsylvania Station in the place marked "Inquiries." You know the Johnnies I mean. You go up to them and say: "When's the next train for Melonsquashville, Tennessee?" and they reply, without stopping to think, "Two-forty-three, track ten, change at San Francisco." And they're right every time. Well, Jeeves gives you just the same impression of omniscience.
As an instance of what I mean, I remember meeting Monty Byng in Bond Street one morning, looking the last word in a grey check suit, and I felt I should never be happy till I had one like it. I dug the address of the tailors out of him, and had them working on the thing inside the hour.
"Jeeves, " I said that evening. "I'm getting a check suit like that one of Mr. Byng's."
"Injudicious, sir, " he said firmly. "It will not become you."
"What absolute rot! It's the soundest thing I've struck for years."
"Unsuitable for you, sir."
Well, the long and the short of it was that the confounded thing came home, and I put it on, and when I caught sight of myself in the glass I nearly swooned. Jeeves was perfectly right. I looked a cross between a music-hall comedian and a cheap bookie. Yet Monty had looked fine in absolutely the same stuff. These things are just Life's mysteries, and that's all there is to it.
But it isn't only that Jeeves's judgment about clothes is infallible, though, of course, that's really the main thing. The man knows everything. There was the matter of that tip on the "Lincolnshire." I forget now how I got it, but it had the aspect of being the real, red-hot tabasco.
"Jeeves, " I said, for I'm fond of the man, and like to do him a good turn when I can, "if you want to make a bit of money have something on Wonderchild for the 'Lincolnshire.'"
He shook his head.