Freud attributed uncovered incest, initially, to real abuse dissociated from self-consciousness, and later, to wishes repressed from consciousness. Dissociation is preferred on theoretical and empirical grounds. Whereas dissociation emerges from double-aspect materialism, repression implicates Cartesian dualism. Several studies suggest that abnormal individuals dissociate trauma from self-conscious source-monitoring, thereby convincing themselves that the trauma is imaginary rather than real, and re-experience the trauma as an unbidden image.