Karl Popper, one of the most influential philosophers of the 20th century, fundamentally challenged conventional views about scientific methodology. The classical positivist approach emphasised knowledge accumulation through observation and induction — drawing general conclusions from specific observations. Popper critiqued this approach, arguing that scientific knowledge is inherently provisional, representing the best understanding available at any moment, subject to revision when new evidence emerges.
At the core of Popper's philosophy is the principle of falsification. He proposed that for a theory to be considered scientific, it must be testable and capable of being proven false. This stands in contrast to the idea that scientific theories are validated through repeated confirmation. Popper argued that science progresses not by proving theories correct but by rigorously attempting to disprove them. For example, the hypothesis "all swans are white" is scientific because it can be falsified by the observation of a single black swan.
This places the acceptance of basic statements, a necessary precursor to action, in a situation akin to trial by jury. Any verdict given is a result of agreement about the evidence presented and prevailing legal code. The verdict is a true statement of fact, but as miscarriages of justice show:
the statement need not be true merely because the jury has accepted it. This … is acknowledged in the rule allowing a verdict to be quashed or revised.
Popper (2010)
This emphasis on falsifiability, rather than verification, allows us to evolve our understanding by discarding theories that do not withstand scrutiny.