An idea is empirically true when it describes the material world directly and survives testing. It is not just logical. It is not just meaningful. It makes contact with reality through observation, measurement, evidence, experiment, or reliable public verification.
In TST, empirically true does not mean absolutely possessed truth. It means our idea lines up with the material world well enough to be trusted within current evidence. Science lives here. It refines these ideas over time, improving the match between our descriptions and reality.
For example, “germs cause disease” is empirically true. So is “Earth orbits the Sun.” These ideas are not true because they are popular, comforting, or traditional. They are true because the material world keeps confirming them.
Empirically true ideas are powerful because reality can push back. When the evidence changes, the idea must adjust. That is not weakness. That is the strength of empirical truth.