 In addition, and more controversially, Rosenthal (2005) thinks that the occurrence of a suitably caused HOT is sufficient for consciousness, even in the absence of any targeted first-order state (usually called ‘targetless’ or ‘empty’ HOTs). So I am undergoing a conscious experience of red provided that I think that I am undergoing an experience of red, even if I am actually in no first-order perceptual state whatever. This aspect of Rosenthal’s view, too, appears optional for an actualist HOT theorist. Such a theorist can—and perhaps should—insist that phenomenally conscious experience occurs when and only when a first-order perceptual state causes a higher-order thought in the existence of that state in a way that doesn’t depend upon self-interpretation. In recent years, the twin problems of misrepresentation between HOTs and their first-order targets as well as targetless HOT cases has led to significant disagreement among HOT theorists (see section 7 below).  