 These observations suggest that qualia, conceived of as the immediately ‘felt’ qualities of experiences of which we are cognizant when we attend to them introspectively, do not really exist. The qualities of which we are aware are not qualities of experiences at all, but rather qualities that, if they are qualities of anything, are qualities of things in the world (as in the case of perceptual experiences) or of regions of our bodies (as in the case of bodily sensations). This is not to say that experiences do not have qualia. The point is that qualia are not qualities of experiences. This claim, which will be developed further in the next section, is controversial and some philosophers deny outright the thesis of transparency with respect to qualia (see Block 1991, 2000; Stoljar 2004; Nida-Rümelin 2007). According to Block, for example, qualia are not presented to us in introspection as intrinsic, non-intentional properties of our experiences. Still it does not follow from this that we are not introspectively acquainted with such properties. For we do know on the basis of introspection what it is like to undergo a visual experience of blue, say. So, if what a state is like is a matter of which intrinsic, non-intentional properties it tokens, then obviously we are introspectively aware of properties of this sort (in the de re sense of ‘of’). On this view, whether qualia are properties of experiences (in particular, intrinsic, non-intentional properties) is a theoretical matter. Introspection does not settle the matter one way or the other.