The Ehrlichs made a number of specific predictions that did not come to pass, for which they have received criticism. They have acknowledged that some predictions were incorrect. However, they maintain that their general argument remains intact, that their predictions were merely illustrative, that their and others' warnings caused preventive action, or that many of their predictions may yet come true . Still other commentators have criticized the Ehrlichs' perceived inability to acknowledge mistakes, evasiveness, and refusal to alter their arguments in the face of contrary evidence. In 2015 Ehrlich told Retro Report, "I do not think my language was too apocalyptic in "The Population Bomb." My language would be even more apocalyptic today."