The New Organon
In addition to the parts everyone knows (“knowledge is power,” “nature to be commanded must be obeyed,” etc.), most of the book is devoted to explaining a long list of specific ways that scientists should observe nature and types of evidence they should collect. In some ways he is amazingly prescient (he figures out, essentially correctly, that heat is a form of motion); in others he is surprisingly behind (he rejected the geocentric theory as late as the 1620s). Most relevant to my current work is his argument for why we should expect progress to be possible: he cites previous inventions and discoveries, including the compass, gunpowder, and the printing press, and extrapolates from these to imagine that there are more inventions waiting to be discovered—which there were.