Scientific theories are used for a variety of purposes. For example, physical theories
such as classical mechanics and electrodynamics have important applications in
engineering and technology, and we trust that this results in useful machines, stable
bridges, and the like. Similarly, theories such as quantum mechanics and relativity
theory have many applications as well. Beyond that, these theories provide us with
an understanding of the world and address fundamental questions about space, time,
and matter. Here we trust that the answers scientific theories give are reliable and
that we have good reason to believe that the features of the world are similar to
what the theories say about them. But why do we trust scientific theories, and what
counts as evidence in favor of them
