This question is very difficult to answer. A lot depends on what one values in philosophy. That said... The most important work in the history of philosophy to have been published in the last decade is J. B. Schneewind's The Invention of Autonomy: A History of Modern Moral Philosophy . Schneewind not only essentially invents the history of modern moral philosophy as a subfield of the history of philosophy, but he also demonstrates the philosophical significance of large-scale, contextual approaches to historical texts. The most significant work in ethics to have been published is T. M. Scanlon's What We Owe to Each Other . It's advances a framework for understanding ethics that could have as great an influence on that field as Rawls' A Theory of Justice had on political philosophy. Richard Moran's Authority and Estrangement: An Essay on Self-Knowledge , is a revolutionary book that should reorient a nest of questions at the intersection of the philosophy of mind, the theory of...

Spinoza's Ethics is an extraordinarily difficult work. I find that it is one of the two most difficult texts written by an early modern philosopher: the other is Hume's Treatise of Human Nature . One reason for the difficulty of Spinoza's text is its style: Spinoza's geometrical method is designed to preclude the reader from attending to anything but the particular propositions of the work, and their proofs, and consequently, it is most difficult for the reader to find her bearings in the work. But Spinoza was not writing in a vacuum. He had been steeped in Descartes' writings, and even wrote a geometrical presentation of Descartes' Principles of Philosophy , the Principles of Cartesian Philosophy . Many of the claims of the Ethics implicitly engage Descartes. Consequently, I have found that it is helpful to read Descartes' Meditations , Part I of his Principles of Philosophy , and the Passions of the Soul , in order to have a point of reference for Spinoza's claims about...

One way to understand the structure of Kant's arguments for the existence of pure forms of intuition (space and time) and the categories of the understanding (such as causality), is to see them as starting from the premise that we have knowledge of a certain sort (for example, knowledge of geometry or arithmetic, or knowledge that things change), and showing that in order for us to have this knowledge, the cognitive faculties must be structured in a certain way. With respect to causality, Kant's claim is that the principle of cause and effect underlies our experience of things as causally related and therefore cannot be derived from that experience, but instead makes it possible. Kant presents the argument for this claim--which is considerably more complicated than I've represented it--in the Second Analogy of experience in the first Critique .

In the first line of the Introduction to the B (second) edition of the first Critique , Kant says that "there is no doubt whatsoever that all our cognition begins with experience, for how else should the cognitive faculty be awakened into exercise" (B1). So experience is necessary in order for human cognitive faculties to operate, and "no cognition in us precedes experience, and with experience, every cognition begins" (B1). Kant goes on to claim in the next paragraph that although knowledge (cognition) begins from experience, there may be some non-experiential component to knowledge provided by the cognitive faculty, "merely prompted by sensible impressions" (B1). He's not assuming that there is such a non-experiential component to knowledge, but simply asking whether there is any such non-experiential component to experience. This is, arguably, the guiding question of the first Critique .

According to Leibniz, mere material things--like food--are not monads. So Leibniz doesn't believe that human bodies are monads, either. But this doesn't dissolve your question. For the fact remains that human beings have experiences as of eating food, and experiences of their bodies, and experiences of their bodies as being nourished by eating food, and so you might well wonder how Leibniz would explain that experience, or any phenomenal experience, for that matter. In order to answer this question, one has to draw a distinction between the phenomenal and metaphysical levels of analysis. At the metaphysical level, according to Leibniz, all there are are monads, which consist of perception and appetition (perception and desires). Leibniz's metaphysics explains all our experience in terms of these perceptions and desires. So, according to Leibniz, alll our ordinary experiences--as of eating food--have their metaphysical basis in the nature of the monad. However, this metaphysical claim does not...

Just a couple of remarks about Descartes. First of all, Descartes doesn't even use the phrase, "I think, therefore I am" in the Meditations ; the phrase only appears in the Discourse on Method . In the Meditations , Descartes writes: "So after considering everything very thoroughly I must finally conclude that this proposition, 'I am, I exist', is necessarily true whenever it is put forward by me or conceived in my mind." What this 'I' is, however, is another matter, which Descartes goes on to examine further in the Second Meditation. In fact, in the Sixth Meditation, Descartes purports to show that the 'I' is a thinking thing. (This raises a vexing question: what does Descartes take the essence of thought to be?) Although 'I am, I exist' is the first truth discovered in the Meditations , it's not the only truth: in the Third Meditation, Descartes purports to discover that God exists; in the Fifth Meditation, he purports to discover the essence of body is extension; in the Sixth...

A version of the story that Alex recounts about the sage is deployed by John Locke in Book II of the Essay Concerning Human Understanding , in order to suggest that the concept of substance makes no sense. Locke attributes the story to an 'Indian philosopher', and says that "the Indian...saying that the world was supported by a great elephant, was asked, what the elephant rested on; to which his answer was, a great tortoise. But being again pressed to know what gave support to the broad-back'd tortoise, replied, something, he know not what. And thus here, as in all other cases, where we use words without having clear and distinct ideas, we talk like children." Most theists would not take such considerations to apply to God, because God is a causa sui , a cause of his own existence. In this respect, God differs from all finite beings. The question now arises what reason there is to believe that God is the one and only causa sui . Arguments have been given to this effect throughout the...

One good test of whether one ought to pursue philosophy is whether one finds oneself staying up at night worrying about philosophical questions. In this vein, I was once told that if I read Thomas Nagel's Mortal Questions and found one essay that kept me up worrying, then I would know that I should go on to graduate school. (Nagel's book is a good test of one's interest because it includes essays on a wide variety of topics, from ethics to the philosophy of mind to free will to the meaning of life.) It is important to try to figure out how much, and why, it matters to one to be a philosopher. After all, philosophy in particular, and academia in general, is not the easiest of professions, and one must be willing to make all sorts of sacrifices, both in graduate school and afterwards, in order to remain in the profession. So one should try to determine whether one is willing to make the sacrifices that may be necessary.

Peter Lipton's reading of Hume is an instance of the skeptical reading of Hume that has prevailed since the eighteenth century. There is, however, another way to read Hume, that has become especially widespread in the last ten years or so, but which also has a long pedigree. On this reading, the naturalist reading of Hume, Hume's question about causal reasoning, the inference from the observed to the unobserved, from impressions to ideas, is a question about which cognitive faculty (reason, the senses, or the imagination) enables agents to draw this inference. Hume's conclusion is that this inference is based on the imagination. (In this way, Hume can be seen as seeking to satisfy his "curiousity...to learn the foundation of this inference.") But this conclusion need not be taken to imply that Hume does not believe that causal inferences cannot be justified or unjustified; indeed, Hume articulates 'rules for judging of causes and effects', and in certain places, seems to suggest that there are norms...

In the early modern period, there was considerable debate about the metaphysical status of miracles. Philosophers as different as Hobbes and Malebranche seem to agree, however, that some event is a miracle if and only if it caused by God's willing that that event take place. On this account, even an event that normally takes place according to natural laws could occur miraculously, if and only if it were a direct effect of God's will. This would be a metaphysical characterization of a miracle. Even granting this definition, of course, there remains a question as to how one could know that some event were a direct effect of God's will. This would be an epistemological question. An alternative definition of miracle, advanced by Leibniz, is that some event is a miracle just in case it cannot be understood by a created mind. According to Leibniz, all natural events can in principle be understood by created minds, provided one has access to the information necessary to understand that event; a...