 Third, it has been suggested that the content of perception is unit-free (Peacocke 1986). If I perceptually represent an object as being a certain distance from me, I do not usually represent that distance in terms of a particular unit (in inches, say, as opposed to centimeters), even though what I represent is a perfectly determinate distance. I simply represent it as being that distance, where the content of my perception specifies the distance. Peacocke (1986, 1989) argues extensively against the possibility of accommodating such unit-free representations in purely propositional terms.