 In addition to the three types of exclusions, central to Śāntarakṣita’s thought on the topic is his unique presentation of representations and the psychological dimensions to his exclusion  theory.[19]  According to Śāntarakṣita, it is our experiences of unifying similarities among representations that gives rise to our conceptual constructs. Mental representations of objects are exclusions because they exclude other representations. These conceptual representations are misconstrued to be the actual objects since the actual objects do not exist in them. For Śāntarakṣita, both the exclusion of that which is other than real particular and the exclusion of that which is other than the representation are both apohas or exclusions. The psychological dimension to exclusion is particularly important in Śāntarakṣita’s apoha theory in that he emphasizes the role of negation in relation to mental representations and mental events in the conceptualizing process. For Dharmakīrti, universals are the objects of concepts. Śāntarakṣita agrees with this point but stresses that the concept is the mental representation or mental event and that is an exclusion, whereas for Dharmakīrti the representations are the basis which supports the exclusions and concepts. For Dharmakīrti, exclusions are conceptual fictions, whereas for Śāntarakṣita they can be real entities.