 In trying to understand Lange’s position, it is helpful to see the kind of view he thinks would escape these worries. Lange considers one version of materialism in his book that he thinks does not undermine itself. This is the position of Heinrich Czolbe, the author of Neue Darstellung des Sensualismus. Lange credits him for being the only one among the materialists to truly face up to the problems regarding perception generated by materialism for itself (Lange 1873–75, 2: 105).