The Essay on the Understanding, produced by an illustrious Englishman, is one of the finest and most admired works of the age. Since I have thought at length about the same subject and about most of the topics which are dealt with in it, I have decided to comment upon it. I thought that this would be a good opportunity to publish something entitled New Essays on the Understanding and to gain a more favourable reception for my thoughts by putting them in such good company. I thought too that I might benefit from someone else's labour, not only to lessen mine (since it is easier to follow the thread of a good author than to do everything by one's own efforts), but also to add something to what he has produced for us, which is always easier than to start from the beginning. It is true that my opinions frequently differ from his, but far from denying the merit of this famous writer I testify in his favour by showing where and why I differ from him, when I find that on certain significant points I have to prevent his authority from prevailing over reason.

Indeed, although the author of the Essay says hundreds of fine things which I applaud, our systems are very different. His is closer to Aristotle and mine to Plato, although each of us parts company at many points from the teachings of both of these ancient writers.