"Falsifiability" - has it been fully discredited? Karl Popper introduced the concept of 'falsifiability' as the touchstone of (modern) science. In essence, Popper claimed that scientists propose theories and (other) scientists seek (experimental, observational) evidence to 'falsify' these theories. Once 'falsified' by a (good) experimental or observational result, the (now falsified) theory is abandoned by (all) scientists, and new theories proposed. And so on ... (of course I'm simplifying, but I hope I've not done too much damage to Popper's idea). Critics of Popper, including Kuhn and Lakatos, fairly quickly showed that this is not at all how science actually works. For example, good observations of the position of the planet Uranus showed it was not at all where it 'should' be, according to Newtonian (gravitational) theory. Rather than 'abandon' Newton, scientists worked on a 'patch' - don't abandon Newton, look for something that will make Newton whole! Years (how many? I should look it up) later, Neptune was discovered, and the anomaly in Uranus' orbit went away. Many years later, a similar situation arose regarding the orbit of Mercury. Again, well after the 'anomaly' was independently verified, and the Newtonian predictions clearly seen to be way beyond the 'error bars' of the observations, scientists didn't regard Newton as 'falsified' ... until a new theory came along! In the history books, it's all clear-cut; but if one doesn't have the benefit of hindsight, then what scientists actually do when faced with good observational/experimental results which, prima facie 'falsifies' a theory is quite different from Popper's description. Modern examples: neutrino flavours (now more or less 'resolved'), dark matter in spiral galaxies (lively debate), the Pioneer anomaly (a true anomaly - the data are good enough to 'falsify' GR/Newton, there are no 'patches', yet no one has 'abandoned' GR!). Curiously, while those who study science have long since put 'falsifiability' into the file 'good idea at the time, didn't pan out', a great many scientists appear to have embraced the idea! At least, they use the term freely when talking about what they do, to non-scientists. Any ideas why this is? But, I've written this from memory, and haven't even checked Popper, let alone his critics. How bad is my memory? If my memory is pretty good, how inaccurate is my summary?