Naval: Where do good explanations come from?
There’s currently an obsession with induction, the idea that you can predict the future from the past. You can say, “I saw one, then two, then three, then four, then five, so therefore next must be six, seven, eight, nine.”
There’s a belief that this is how new knowledge is created, that this is how scientific theories are formed and this is how we can make good explanations about the universe.
What’s wrong with induction, and where does new knowledge actually come from?
Brett: You mentioned the black swan earlier, and I’d like to go back to that. The black swan is an example people have used over the years to illustrate this idea that repeatedly observing the same phenomena over and over again should not make you confident that it will continue in the future.
In Europe we have white swans, so any biologist who’s interested in birds would observe white swan after white swan and apparently conclude that, therefore, all swans are white. Then someone travels to Western Australia and notices swans there look otherwise identical to the ones in Europe—but they’re black.
Let’s consider another example of induction.
Ever since the beginning of your life, you have observed that the sun has risen. Does this mean that scientifically you should conclude that the sun will rise tomorrow and rise every day after that? This is not what science is about.
Science is not about cataloging a history of events that have occurred in the past and presuming they’re going to occur again in the future.
Science is an explanatory framework. It’s an error-correcting mechanism. It’s not ever of the form, “The sun always rose in the past, therefore it will rise in the future.”
There are all sorts of ways in which we can imagine the sun won’t rise tomorrow. All you need to do is to take a trip to Antarctica, where the sun doesn’t rise at all for some months of the year.
If you go to the International Space Station, you won’t see the sun rise and set once per day. It will rise and set repeatedly over the course of your very fast journey around the Earth.