Empiricism Without the Senses: How the Instrument Replaced the Eye

The optical instruments developed through the seventeenth century allowed peering into the very far and the very small; a spectacle never before experienced. The telescope, and later the microscope, was now expected to answer fundamental questions and resolve cosmological riddles by direct observation into the foundations of nature. But this ability came at an unexpected price and with unexpected results. For Kepler and Galileo, the new instruments did not offer extension and improvement to the senses; they replaced them altogether. To rely on their authority was to admit that the human eye is nothing but an instrument, and a flawed one at that. Rather than the intellect’s window to the world, the human senses became a part of this world, a source of obscure and unreliable data, demanding uncertain deciphering. Accurate scientific observation meant that we are always wrong.