I previously had read Tom Sorrell's book on Hobbes and had very much enjoyed that. I learned a great deal from it and was impressed by its depth and range. I did not learn nearly as much from this book. It is not that the book is misconceived or poorly informed. It is simply not as well executed as his Hobbes book. It isn't a question of length. There is an absolutely outstanding introductory book on Descartes by John Cottingham, perhaps the top English language Descartes scholar of our time, Descartes, that is both enormously informative and exceptionally well written. I found this short book by Sorrell to be wide-ranging but opaque, and less illuminating on various ideas and concepts than I would have liked. If it weren't for the hefty price of the Cottingham book, I would strongly recommend it over this one.
The strong point of this book is that it takes a balanced approach to Descartes's philosophy. Many books on Descartes emphasize the philosophy over the scientific to such a degree that it drops out of consideration as an issue. Some undergraduates, having read the MEDITATIONS in a freshmen philosophy class, are unaware of Descartes's importance as a mathematician or physicist. Sorrell does an excellent job of placing all of Descartes's though within his scientific agenda. Descartes was not a philosopher who dabbled with science, but a scientific theoretician who was forced to metaphysical reflections. Though Sorrell is clear on noting that physicists and scientists did not exist as such; what we would call scientists were at the time known as natural philosophers. The problem with the book is not the breadth; that is actually its strength. The problem is the lack of clarity in the details. Too many concepts are mentioned in their contexts, without fully explaining that context. Because I've read a good deal on Descartes (actually, two graduate level courses on his work), I kept thinking that this was missing here or that lacking there.
The one thing that I found did regret in setting the overall context of Descartes work was the degree to which it was driven by theological concerns. Descartes was, as Sorrell points out, a critic of the Scholastic school that dominated Catholic education at the time. Descartes saw himself as opposing the Aristotelianism embedded in Scholastic (Thomist) thought by resurrecting Augustinian (hence, Platonic) thought. So when I say that Sorrell is good as setting the context of Descartes's thought, it was in terms of his scientific goals. Like many Decartes scholars, Sorrell neglects the theological side of his work, though it has been dealt with more thoroughly in the past couple of decades by several French and a few English-language scholars. Still, it is a book worth reading, though if you have the money or access via a library to the Cottingham book I noted above, I would recommend that instead.