According to the thesis of transparency, subjects can attend only to the representational content of perceptual experience, never to the intrinsic properties of experience that carry this representational content, i.e., to “mental paint.” So far, arguments for and against transparency were conducted from the armchair, relying mainly on introspective observations. In this paper, we argue in favor of transparency, relying on the cognitive neuroscience of attention. We present a trilemma to those who hold that attention can be directed to mental paint. Such attention is either first-order sensory, higher-order cognitive, or higher-order sensory attention. We argue that the notion of first-order sensory attention to mental paint is incompatible with the neuroscience of sensory attention; that higher-order cognitive attention to mental paint is irrelevant to transparency; and that the notion of higher-order sensory attention to mental paint has an apparently incoherent prediction. Via elimination, these considerations support the thesis of transparency.