Sometimes, if you're lucky as a historian, you find a bit of evidence which illuminates a big idea. That happened to me this week in the Pepys Library at Magdalene College, Cambridge.
The thought uppermost in my mind was how odd it is that non-scientists think of science as being about certainties and absolute truth. Whereas scientists are actually quite tentative - they simply try to arrive at the best fit between the experimental findings so far and a general principle.
The manuscript I found was a ship's journal kept by a 17th Century English sea captain, who had offered to carry some state-of-the-art scientific equipment on a voyage to the west coast of Africa and back - two new pendulum clocks.
