Experiment!: Planning, Implementing and Interpreting

4.2 Experiment or Hoax?

Marin Mersenne, a contemporary of Galileo, was a friar and scientist who corresponded regularly with many of the leading scientists of his day. He had seen references to the experiment on the inclined plane already before the publication of Two New Sciences and had tried to perform it himself. Although Galileo had mentioned the experiment in other places, he had never given a description as detailed as that in his last book. We may even suspect that the detailed description there was an answer to Mersenne's criticism. As Mersenne had not succeeded in reproducing the experiment, he regarded it as incapable of founding a science. He even doubted that Galileo had performed it at all [3].

Perhaps inspired by Mersenne's failed attempts, the philosopher Alexandre Koyré provided outspoken criticism of Galileo's experiment in a 1953 paper [4]. Koyré was an eager advocate of the view that theory must precede observation in science and, judging from the paper, he even seems to have thought that empirical investigation was less dignified than theoretical speculation. Galileo's water clock was too primitive to have played a central role in the experiment, he thought. It lacked both precision and theoretical refinement. Indeed, he thought that the whole experiment was too crude to provide useful results. This was partly because he thought that Galileo had based it on faulty assumptions, and partly because of the “amazing and pitiful poverty of the experimental means ...