 It should be noted that if the core commitment of sense-datum theories is that one immediately perceives mental objects in experience, then sense-datum theories are neutral on whether experiences are assessable for accuracy. From the fact that one perceives (or immediately perceives) a particular object (be it a public object or a private mental one), nothing at all follows about whether the experience of so perceiving is assessable for accuracy or not (for more on sense-datum theories, see the entries on  sense data  and the  problem of perception).  Jackson (1977) defends a version of the sense-datum view according to which experiences are not assessable for accuracy.