Measurements of the isothermal remanent magnetization Mr and the dc demagnetization remanence Md have been made on single crystals of YBa2Cu3O7 with the applied magnetic field parallel to the c axis. Plots of Md vs Mr indicate the presence of interactions when the usual interpretation developed for ferromagnetic systems is applied. However, this interpretation neglects the intrinsic response of a superconductor to expel the flux with supercurrents. It is found that the plots, although suggesting repulsive interactions, are qualitatively explained by the Bean critical state model. In addition the use of the Md vs Mr plots in connection with the Bean model provides an alternative technique to determine critical currents.