  The memory resistor abbreviated memristor was a harmless postulate in 1971.
In the decade since 2008, a device claiming to be the missing memristor is on
the prowl, seeking recognition as a fundamental circuit element, sometimes
wanting electronics textbooks to be rewritten, always promising remarkable
digital, analog and neuromorphic computing possibilities. A systematic
discussion about the fundamental nature of the device is almost universally
absent. This report investigates the assertion that the memristor is a
fundamental passive circuit element, from the perspective that electrical
engineering is the science of charge management. With a periodic table of
fundamental elements, we demonstrate that there can only be three fundamental
passive circuit elements. The ideal memristor is shown to be an unphysical
active device. A vacancy transport model further reveals that a physically
realizable memristor is a nonlinear composition of two resistors with active
hysteresis.
