A scientific theory must be supported by evidence gathered thus far. Additionally, when data is collected that contradicts a scientific theory, we need to form a new theory that should not only account for the new phenomenon but also explain all the data points that supported the old theory. Therefore, science typically refines existing theories rather than beginning anew. 1

For instance, while the notion that “Earth is a perfect sphere” is wrong, it still serves as a significantly better approximation than “Earth is flat.”

This is similar to how a person learn. New information we learned usually won’t invalidate everything we know beforehand.

Footnotes

  1. How to Think Straight About Psychology Chapter 2 (note)