Themistius, another influential commentator on this matter, understood Aristotle differently, stating that the passive or material intellect does "not employ a bodily organ for its activity, is wholly unmixed with the body, impassive, and separate [from matter]".[37] This means the human potential intellect, and not only the active intellect, is an incorporeal substance, or a disposition of incorporeal substance. For Themistius, the human soul becomes immortal "as soon as the active intellect intertwines with it at the outset of human thought".[35]