CHAPTER Moving on: Applications and Beyond 9 Machine learning is a burgeoning new technology for mining knowledge from data, a technology that a lot of people are beginning to take seriously. We don't want to oversell it. The kind of machine learning we know is not about the big problems: futuristic visions of autonomous robot servants, philosophical conundrums of con- sciousness, metaphysical issues of free will, evolutionary (or theological) questions of where intelligence comes from, linguistic debates over language learning, psy- chological theories of child development, or cognitive explanations of what intel- ligence is and how it works. For us, it's far more prosaic: Machine learning is about algorithms for inferring structure from data and ways of validating that structure. These algorithms are not abstruse and complicated, but they're not completely