Can anyone tell me how a constructivist philosopher would view concepts in classical thermodynamics, say like the state variables pressure, temperature, internal energy, and entopy? I read in Wikipedia that "Constructivists maintain that scientific knowledge is constructed by scientists and not discovered from the world ". These days most physicists regard such variables as quantifying macroscopic emergent phenomena. I suppose that from a constructivist perspective thermodynamic phenomena and their quantitative descriptions are invented rather than discovered. But maybe this is wrong? I'd like to know what the views of folk in this forum are. I've chosen thermodynamics because it's a closed subject in physics that many are familiar with, which was developed long, long ago. Arguments about it's nature are, I hope, not likely to raise the hackles of active researchers in thermodynamics, of which I suppose there are, by now, very few, if any.