We evaluate a mean field method to describe the properties of the ground state of the Ising chain in
a transverse magnetic field. Specifically, a method of the Bethe–Peierls type is used by solving
spin blocks with a self-consistency condition at the borders. The computations include the critical
point for the phase transition, exponent of magnetisation and energy density. All results are
obtained using basic quantum mechanics at an undergraduate level. The advantages and the limitations
of the approach are emphasised.