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Intentionality/about/aboutness/MillikanVsTradition: Intentionality is not transparent: many processes that are "about" something in the sense that their users are not aware of them.
E.g. von Frisch knew what a bee dance is about, the bees do not know. Bees react only appropriately to bee dances.
Thought: requires that the referent is identified.
R. G. Millikan
Language, Thought, and Other Biological Categories: New Foundations for Realism Cambridge 1987