An ardent young astronomer, not very long ago, made a supposed discovery which gave him great happiness for a time. A powerful new telescope had just been made ready for use, and he was the first to scan the heavens through its lens. He had no sooner put his eye to the tube than a wonderful object, a blue star, arrested his gaze. It was incredible. He withdrew his eyes in order to reflect for a moment. Then he gazed again, and, wonder of wonders, the blue planet was still shining far away in the spacial depths. As he continued to gaze at the brilliant phenomenon a wave of joy and pride surged through his veins. He had discovered something which all the learned astronomers of the past and present had quite overlooked. He could gaze at nothing else, he could think of nothing else. He might remove his eyes for a few seconds to entertain a bit of scientific skepticism, but soon he cherished no doubts whatever, and foresaw his name enrolled imperishably with those of Kepler, Galileo, Newton, and Herschel. But the young astronomer was doomed to be robbed of his fine fancies by a rude awakening. The blue star which was to have lighted him on to undying fame turned out to be only a common star after all, for it was found that a fault in the achromatic lens had produced the unusual color.
This fitly illustrates the uncertainties which accompany inductive reasoning and the propositions seeming to flow therefrom, which have been employed in physical science, sometimes altogether too boastingly, especially since the day of Francis Bacon. The physicists assert that they accept nothing as true until some indubitable fact of discovery justifies the proposition. This is a very alluring proposition, and many have been led by it into the superficial notion that the inductive method of reasoning is the only safe method for the ascertainment of truth.
For several years the writer had been a reader of the literature of what is known as physics, or physical science, and he was led to adopt the notion that physical facts, and inductive reasoning based on such facts, afford the only reliable means of acquiring truth, and that the deductive method of reasoning was unfit for such purpose and chiefly belonged to the obscure region of metaphysical subtleties.
