ABSTRACT
If the qualitative character of blueness were itself mentalistic—a quale—then ‘that which makes the sensation of blue a mental fact’ could hardly be said to ‘escape us’. Moore’s point here is that the qualitative blueness of the blue thing is not itself mentalistic; it is an external characteristic of the object out there. Traditionally a natural reaction at this point has been to appeal to some non-representational aspect of visual experience, such as a ‘sensation’, in order to explain the sense in which redness is there in the experience. Representations merely tell readers what is out there; sensations make the scene come alive, pump colour into it. In an influential discussion, Christopher Peacocke gave one of very few serious attempts to provide an explicit vocabulary for talking about colour sensations:It will help at this point if we introduce a simple piece of notation. The possibility of spectrum inversion is usually taken as datum in discussions of colour and colour experience.
