Am I guilty, then, as has been charged, of preferring the deductive method of reasoning to the more modern and more scientific inductive method? But I doubt if the inductive method would avail one in trying to prove that the old cow really jumped over the moon. We do deny certain things upon general principles, and affirm others. I do not believe that a rooster ever laid an egg, or that a male tiger ever gave milk. If your alleged fact contradicts fundamental principles, I shall beware of it; if it contradicts universal experience, I shall probe it thoroughly. A college professor wrote me that he had seen a crow blackbird catch a small fish and fly away with it in its beak. Now I have never seen anything of the kind, but I know of no principle upon which I should feel disposed to question the truth of such an assertion. I have myself seen a crow blackbird kill an English sparrow. Both proceedings I think are very unusual, but neither is antecedently improbable. If the professor had said that he saw the blackbird dive head first into the water for the fish, after the manner of the kingfisher, I should have been very skeptical. He only saw the bird rise up from the edge of the water with the wriggling fish in its mouth. It had doubtless seized it in shallow water near the shore. But I should discredit upon general principles the statement of the woman who related with much detail how she and her whole family had seen a pair "of small brown birds" carry their half-fledged young from their nest in a low bush, where there was danger from cats, to a new nest which they had just finished in the top of a near-by tree! Could any person who knows the birds credit such a tale? The bank-teller throws out the counterfeit coin or bill because his practiced eye and touch detect the fraud at once. On similar grounds the experienced observer rejects all such stories as the above. Darwin quotes an authority for the statement that our ruffed grouse makes its drumming sound by striking its wings together over its back. A recent writer says the sound is not made with the wings at all, but is made with the voice, just as a rooster crows. Every woodsman knows that neither statement is true, and he knows it, not on general principles, but from experience--he has seen the grouse drum. Birds that are not flycatchers sometimes take insects in the air; they do it clumsily, but they get the bug. On the other hand, flycatchers sometimes eat fruit. I have seen the kingbird carry off raspberries. All such facts are matters of observation. In the search for truth we employ both the deductive and the inductive methods; we deduce principles from facts, and we test alleged facts by principles.