 Harman’s emphasis here is on the negative thesis, which goes back at least to Moore (1903; though Moore does not unambiguously endorse it). The view that it is impossible to attend directly to perceptual experience has been especially stressed by Tye (1995, 2000, 2002; see also Evans 1982; Van Gulick 1993; Shoemaker 1994a; Dretske 1995; Martin 2002; Stoljar 2004), and directly conflicts with accounts according to which we learn about our sensory experience primarily by directing introspective attention to it (e.g., Goldman 2006; Petitmengin 2006; Hill 2009; Siewert 2012; and back at least to Wundt 1888 and Titchener 1908 [1973]).