If we have a metal wire and a magnetic field "inside" it, when the flux of the magnetic field changes, then the wire "reacts" by "creating" an induced current. After learning this law, it eventually came to my mind the question: how does the wire know that the magnetic field flux has changed? I mean, in order to note the change, the wire somehow needs to have memory: "the magnetic field flux was x one second ago, and now it's x+dx... ok, it's time to induce a current". Inanimate objects, such as wires, i.m.o. only know what happens around them instantly, so i find very hard to understand the fact that an inanimate object can detect a change of a physical variables in two different moments.