 In the philosophy literature, cases of perceptual learning have often been used to show that through learning we come to represent new properties in perception, which we did not represent prior to learning. Siegel (2006, 2010), for instance, asks us to suppose that we have been tasked to cut down all and only the pine trees in a particular grove of trees. After several months pass, she says, pine trees might begin to look different to us. This is a case of perceptual learning, a long-term change in our perception following practice or experience with pine trees. Siegel uses the case to argue that perception comes to represent kind properties, like the property of being a pine tree. The idea is that the best way to explain the change in perception is that perception represents the property of being a pine tree after, but not before, learning takes place. That property becomes part of the content of perception: it comes to be presented in perceptual experience (for more background on the contents of perception, see Siegel 2016).