Actor-network theory always struck me as slight of hand. Latour was studying scientists, who rightly objected to the science-is-just-a-story-like-any-other sort of theory of science that was fashionable in the tradition he came from, which was inconvenient for him because it's hard to gain the trust of people who think you're a crazed solipsist. He still thought science was a tool of The Man that needed to be deflated. His solution is to make a theory that grants the existence of atoms and gravity and such... in the same sense as it grants the existence of god, the devil, the flying spaghetti monster, good and bad vibrations, and anything else anyone claims to believe in. So his is exactly the same sort of theory, just framed so that it does not sound so ridiculous when he interacts with scientists, as long as he doesn't elaborate too much.