The Review of Metaphysics

In The Two Greatest Ideas Linda Zagzebski takes the reader on an idiosyncratic yet illuminating jaunt through intellectual history, charting the ascendency, implications, and challenges of two major themes in Western thought. The first of these two ideas is that our minds can grasp the world: that there is an objective world and that humans can understand it. The second is arguably a corollary to the first: that the human mind can grasp itself.

Much of the book focuses upon the way in which these two ideas are in tension. Zagzebski structures this story as a story about which of these two ideas has primacy. She argues that it was the realization that in grasping oneself as a mind impinged upon by external forces whose origins can only be inferred, that the second idea came to undermine our faith in the first. In the last century, she continues, even the second idea has come undone. If knowledge of the outer world cannot ground knowledge of the inner, and the inner cannot support the outer, knowledge itself becomes destabilized. Zagzebski traces many of our modern-day maladies to our failure to successfully integrate these two themes.

Although this book is about philosophy, it is more a broad-brush sketch of intellectual history than a philosophy book. It does not hold itself to the standards of rigor characteristic of most philosophical texts. That rigor would presumably detract from its appeal to nonphilosophers, clearly its intended audience. To a philosopher, however, this free-wheeling style of exposition and argument can be irritating. For example, the nature of the two ideas remains somewhat ambiguous: Are the ideas about the possibility of understanding the world or of completely understanding it or of reaching ultimate truth or about the priority or foundations of knowledge? At various points, each of these is considered, but although each of these ideas is importantly distinct, these distinctions are not [End Page 613] clearly identified in the text. Even more frustrating, nothing is said about the concept of grasping: What does it mean to grasp the world, our minds, or our selves? One worries that there are not just two ideas here, but many, and that their influence is far more diffuse than the author wants us to accept.

On the other hand, one of the refreshing things about this book is that although it concerns most centrally themes and commitments of Western thought, Zagzebski frequently stops to compare these commitments to related commitments (or their absence) in non-Western philosophical traditions, to show that certain ideas are either universal, or alternatively, that they aren't. For example, when considering the difficulty the West has had in integrating the subjective and objective, or in explaining consciousness given commitments to naturalism or physicalism, she points out that in native American, Asian, and African philosophies, the physical world is permeated with mind or spirit: No such dichotomy is ever contemplated. These kinds of observations can be eye-opening, and without mention it might never occur to those of us so steeped in Western traditions that there are other possible ways to view the world. Additionally, Zagzebski draws her examples from both the analytic and Continental philosophical traditions, adopting an inclusive approach encompassing both traditions.

Earlier I called the book idiosyncratic. I mean that characterization as descriptive but not pejorative. Certain thinkers or types of thinkers play an outsized role in her discussions: Zagzebski is heavily influenced by Christian philosophers from St. Augustine and Aquinas to Plantinga, and by the ancients. Kant and Descartes play predictably central roles as well, but many thinkers who have written on these topics more recently, especially from the analytic tradition, are noticeably absent from the discussion. Also idiosyncratic are her choices of illustrations from science, art, and culture. She pulls from sources as diverse as Pythagoras, Kepler, and modern string theory, and underscores structural...