“No amount of observations of white swans can allow the inference that all swans are white, but the observation of a single black swan is sufficient to refute that conclusion.”
One of biggest names in the field of philosophy has to be David Hume. Born in Scotland during the 18th century, Hume is known for his empiricism (theory of knowledge) and skepticism. In the quote above, he provides us with a very common logical fallacy. Many people assume that if they see a lot of something, it must true universally.
However, that is not at all the case. Just because you’ve seen a lot of white swans doesn’t not mean that you can infer that all swans are white. Seeing just one non-white swan, though, can render that conclusion incorrect. You may have your rules, but you can fully expect to discover exceptions to those rules.
The trouble is that when it comes to political policy and other major decisions, inference can oftentimes be all we have. Similarly, we may only know of correlation, hoping to extrapolate causation. At the same time, we have to recognize that this inherently faulty logic. When it comes to knowledge, very little is absolutely certain.