From Plato right through to the 19th century, philosophers approached questions of ethics and knowledge through an understanding of how the mind worked. In Bacon's time, this took the form of what's now called faculty psychology, which saw the functioning of the mind in terms of overlapping and interrelated mental capacities. The faculty of understanding apprehended the direct forms of things, which was then analysed by reason, and, with the aid of imagination, used to direct and influence the appetite and will. However, this view was so common that Bacon often takes it for granted - he assumed that his readers would be familiar with this psychological picture. Wallace therefore does an invaluable service in filling in the background to Bacon's philosophy - and that of Hobbes, Descartes, Locke and other near contemporaries. This is a fascinating picture in itself, and presents an interesting contrast to the modern view of the mind via neuroscience, which is perhaps not so easy to get a handle on. Arguably, we now no longer have a common language of psychological action and motivation that can act as a basis for popular understanding, for the discussion of ethics and self-knowledge. Such pictures as do exist seem vague and imprecise - we talk more generally of mind and emotion and desire, whereas the classical picture was both more holistic and more precise.

Gareth Southwell is a philosopher, writer and illustrator.