The connection between scientific knowledge and our empirical access to realityis not well explained within the structuralist approach to scientific theories. I arguethat this is due to the use of a semantics not rich enough from the philosophical pointof view. My proposal is to employ Sellars–Brandom's inferential semantics to understand how can scientific terms have empirical content, and Hintikka's game-theoretical semantics to analyse how can theories be empirically tested. The main conclusions are that scientific concepts gain their meaning through `basic (...) theories' grounded on `common sense’, and that scientific method usually allows the pragmatic verification and falsification of scientific theories. (shrink)