The astrophysicist Carl Sagan liked to say that extraordinary claims require extraordinary evidence. But Dennis Danzik’s assertions blow past extraordinary and motor right on to fantastic.

Mr. Danzik, the science and technology officer for Wyoming-based Inductance Energy Corp., says he has invented a magnetic generator, a flywheel system that extracts usable energy from the interplay of exotic magnets—also known as a free-energy device, a cousin to the fabled perpetual-motion machine.

Mr....