" Philosophers have long regarded intentionality as a puzzling phenomenon, for it is hard to see how it can arise in a purely physical world. After all, mental states presumably depend ultimately on the brain, and thus on neurons and their interconnections, but neurons do not seem to be ‘about’ anything, nor to have representational content. So how can intentionality fit into the world that modern science describes?

In the 1980s, the philosopher Ruth Millikan suggested an ingenious solution to this puzzle by drawing on Darwinism. To illustrate her basic idea, consider the honey bee’s waggle-dance. This is the complex figure-of-eight dance that honey bees use to signal to their hive mates the location of a food source. Since the bee’s dance has been shaped by natural selection for a particular purpose—correctly indicating where the food is—this allows us to discern a kind of proto-intentionality in the waggle-dance. We can sensibly say that a particular dance routine means that the food is located 30 metres away in the direction of the sun, in the sense that the biological function of the dance is to induce its hive mates to fly to this location. The bee’s waggle-dance is thus capable of misrepresentation—for the food may not actually be in this location, for example if the bee has accidentally performed the wrong routine. In short, Millikan’s idea is that representational content may be rendered scientifically respectable by reducing it to biological function, a notion which plays a bona fide role in evolutionary biology. This bold attempt to naturalize intentionality is controversial, but it illustrates how a biological perspective can help illuminate an old philosophical issue. "

― Samir Okasha , Philosophy of Biology: A Very Short Introduction