I can never bring you to realize the importance of sleeves, the suggestiveness of thumb-nails, or the great issues that may hang from a boot-lace.

Still, it is an error to argue in front of your data. You find yourself insensibly twisting them round to fit your theories.

Well, I'm a bacteriologist, you know. I live in a nine-hundred-diameter microscope. I can hardly claim to take serious notice of anything that I can see with my naked eye.

I said that he was my superior in observation and deduction. If the art of the detective began and ended in reasoning from an armchair, my brother would be the greatest criminal agent that ever lived. But he has no ambition and no energy. He will not even go out of his way to verify his own solutions, and would rather be considered wrong than take the trouble to prove himself right.

How sweet the morning air is! ...How small we feel with our petty ambitions and strivings in the presence of the great elemental forces of Nature!

Women are naturally secretive, and they like to do their own secreting.

You cannot see the lettuce and the dressing without suspecting a salad.