The Falsification of Knowledge

Popper understood that knowledge is real and possible. But many people think he rejected knowledge because they think his entire philosophy is about falsificationism. Everything we know is always conjectural, which is to say, tentative. It contains truth, but it's not the final truth. If your favourite beautiful theory is slain by an ugly fact, you shouldn't be able to change it just a little bit in order to explain what went wrong.