Truth

An observation by Stephen Jay Gould:

In science, “fact” can only mean “confirmed to such a degree that it would be perverse to withhold provisional assent.” (Evolution as Fact and Theory, pp.254–55)

I'm fond of that quote because every word counts, and because it makes clear that physicists are not after truth, but instead quantitative rules of thumb for dealing with the behaviour of the universe. The most useful such rules are those we have repeatedly tried to falsify by observation, but which have nevertheless proven reliable (either universally so, or in a well-defined set of limited circumstances). Truth we leave to the mathematicians, who are welcome to it. -- Tom Yates