This article develops a perspective on big data in education, drawing on a broadly liberal conception of education's primary purpose. We focus especially on the rise of so-called learning analytics and the associated rise of digitization, which we evaluate according to the liberal view that education should seek to cultivate individuality and proceed partly by way of experimentation and with an emphasis on civic education. Our argument is not that the use of big data is wholly out of place in education. Indeed, it might have significant value in pursuit of certain educational aims. Nevertheless, the liberal conception shows how education is distinct from other domains in which big data are being applied, in ways that suggest that considerable caution must be exercised when they are used in educational contexts.