This article addresses two issues: the distinction between objective and subjective measures and the directness of such measures. It is argued that the distinction is unambiguous only when based on a methodological criterion rather than a semantic one. Different senses of directness are discussed: metaphysical, methodological, semantic, and causal.

The article suggests answers to the questions of how we can arrive at an unambiguous characterization of consciousness, whether conscious states are coextensive with subjective ones, and whether consciousness can be graded and multidimensional at the same time. As regards the first, it is argued that a general characterization of consciousness should be based on its four dimensions: i.e., the phenomenological, semantic, physiological and functional ones. With respect to the second, it is argued that all informational states of a given (...) organism are subjective, but not all are necessarily conscious. Finally, where the third question is concerned, in each of the four dimensions of consciousness a graded element is identified: quality of information in the phenomenological one, abstractness in the semantic one, complexity in the physiological one, and usefulness in the functional one. The article also considers certain consequences of the solutions proposed, as well as some practical applications of the 4D-view of consciousness. (shrink)