It is a construction. Because its the best social construction anyone has devised for testing theories about the world, showing their limits, and coming up with better ones. Unless one wants to treat it as a religion and worship scientists as priests, surely any thinking person has a right to ask. Particularly when, on the face of it, scientists don't always seem to be working for the common good. Sokal's examples of 'good science' are the search for a cure for AIDS and research on global warming.
Many scientists question the priorities and purposes of particular branches of science.
But many are beneficiaries of military and corporate funding that to others may appear questionable. As part of a movement that has asserted the rights, not just of other scholars, but of ordinary citizens to ask such questions, Social Text co-editor Andrew Ross has copped a lot of flack from scientists. He is vilified in the book Higher Superstition that Sokal has quoted with approval. Sokal wants us to believe that his views as they appear in Social Text are a put on, but that he is being honest when he says that he too is critical of the excesses of science. He seems to want to join the ad hominen attack on the critics of science rather than face up to the notion that science may not be above public scrutiny.