I have recently had two thoughts about this famous old saying of Newton, who is not forgotten. First, when standing on the shoulders of giants, we do not build a tower; we build a pyramid, like those circus acrobats you sometimes see. The base is much larger than the tip, which makes for stability; and there is mutual support. Any particular result depends on a lot of other results, and if you adjust one you may have to adjust others, as when Millikan got the wrong value for the charge of the electron because he had the wrong value for the viscosity of air. But this also means that you cannot knock out one paper and make a whole structure come tumbling down, as cretinists and global-warming deniers sometimes try.
The second is this. Newton was not being modest when he said that; he was being snarky towards Hooke (who is not forgotten), who had accused him of stealing results and who was very short – no giant, in Newton’s phrase. But never mind that; we have remembered the image and forgotten the snark, and rightly so. But we have also forgotten why it is such an arresting image, and I sum this up in an aphorism: The purpose of standing on the shoulders of giants is not to praise the giants, but to see further.