This is an absolute work of art, if you take the time to digest what they've done. In order to articulate a model of cognition, they have implemented a probabi

This is an absolute work of art, if you take the time to digest what they've done. In order to articulate a model of cognition, they have implemented a probabilistic version of Scheme, that compiles to JavaScript, and that allows for forward and reverse simulation in the browser. Given a model that can simulate forward from causes to effects, you can simulate backward (perform inference) from observed effects to causes, all inline throughout the book.