Written by David Deutsch.
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Extrapolating from past data points is not an explanation. Building your confidence that something that will happen—like Bayes Theorem—is useful for descrete, observable problems, but fails to reveal the truth. It’s the equivalent of saying “because it’s always been that way” which is a flawed way of reasoning about the world.
The process of seeking out good explanations is error correcting. It is tolerant of dissent with a healthy dose of skepticism and distrust of authority. It means that explanations are rejected when they are contradicted by better explanations.
A popular view of the environment, “Spaceship Earth”, is that the planet provides just the right biosphere to support human life. That is misleading because humans are actually ill suited to living in most places. Take for example living in New York—you would freeze to death come winter if not for shelter, clothing, access to clean water, and food. This is technology that humans created to transform inhospitable environments into systems that support human life.
A good explanation can not be modified or molded to fit when new information contradicts it. It predicts situations that are both known and unknown. The domain of it’s meaning and applicability is not yours to specify.
A parochial error happens when you falsely believe that something in your narrow view of the world applies more broadly than it does. For example, thinking the seasons everywhere around the earth in the same way as your home town because that’s what you personally experience.
One way to answer “how do we know…?” is to justify one’s belief by reference to an authoritative source or cornerstone of knowledge. This is, in effect, saying “by what authority do we claim…?” which seeks endorsement in order to have certainty. Justificationism as a theory of knowledge therefore resists change (or at least delays in a form of path dependence).