it's hard to conclusively say we'll never discover a perpetual motion machine

That heat is energy escaping,and it would keep leeching out,reducing the energy available to move the system itself until the machine inevitably stopped.So far, these two laws of thermodynamics have stymied every idea for perpetual motion and the dreams of perfectly efficient energy generation they imply.Yet it's hard to conclusively say we'll never discover a perpetual motion machine because there's still so much we don't understand about the universe.