Sometimes life feels unsatisfying. A shallow version of the feeling comes and goes with ordinary disappointments. You look at the burned enchiladas you've pulled from the oven, and reflexively your shoulders slump.
A deeper version of the feeling is possible. It could be prompted by something like a burned dinner, but more typically it is brought on by the thought of death, someone else's or the prospect of your own. You ask yourself, "is this all there is?" Doubt arises that life has meaning or value. Existential anxiety is one name for this feeling.
Religion takes this kind of anxiety seriously. It says yes, mundane existence is lacking. But it also also says, good news: there is a means of addressing it called salvation. The means of salvation differ from one religion to another. We typically think of salvation as involving non-rational commitment (eg, faith), and for that reason many people don't find it credible.
Siderits points out that not all religions are like that. Some religions claim salvation can be arrived at by rational investigation of the world: for example, Indian Buddhism and medieval Islam. This book surveys the rational means of salvation proposed by various traditions within Indian Buddhism.
Buddhism summarizes our situation with the Nobles' Four Truths:
(NT1) There is suffering.
(NT2) The suffering originates from known causes.
(NT3) The suffering will cease when the causes are removed.
(NT4) There is path that can be followed to remove the causes.
Each of these four truths is elaborated. The suffering mentioned in (NT1) can be categorized into three kinds, the deepest of which is a cosmic ennui like the existential anxiety mentioned earlier. The origin in (NT2) is a chain of causes and effects with twelve links, the first of which is our ignorance; and in particular, we are ignorant of three characteristics of reality, the third and deepest of which is "non-self" (more on this in a sec). Siderits doesn't say much about (NT3), but the suggestion seems to be that ridding ourself of ignorance (the first link in the chain of cause and effect) is going to be key. Finally, the path mentioned in (NT4) is the Nobles' Eightfold Path, the first "step" (a slight misnomer; again, more on this in a sec) of which is indeed coming around to the right view of reality, including the fact of non-self mentioned above.
Siderits points out that the eight steps in the path don't have a simple ordered and directed relationship ("first this, then that"). Instead they are mutually reinforcing. To understand how the mutual reinforcement works, it is helpful to think of each of the steps as pertaining to either wisdom, morality, or meditative practice. With those categories in mind, you can think of the mutual reinforcement of the steps like so:
* Attaining wisdom clarifies why you should be moral; and moral conduct prepares the mind for wisdom.
* Wisdom and morality in combination deepen our understanding in a way that facilitates meditation.
* Meditation in turn strengthens our appreciation of wisdom and morality.
Some of this is practical advice grounded in psychology. I don't have any experience with meditation, and I don't have any reason to doubt it could be helpful.
From a philosophical perspective I am with Siderits in thinking the really interesting stuff has got to be the doctrine of non-self that, allegedly, would free us from existential anxiety or cosmic ennui. What is this doctrine and what the arguments for it?
Across the different traditions he surveys, there are different formulations of the non-self doctrine with different supporting arguments. If I were interested in Buddhism as such, I would take more care to represent the arguments faithfully, but instead I'm just going to formulate something borrowing from them and Siderits explanations that seems close in spirit and at least gives me pause -- here goes:
Our existential suffering arises from a misperception. On examination the word "I" is merely a convenient designator. If it refers to anything, it is a complex of on-going, overlapping, time-limited processes rather than anything ultimately real and enduring. No part of you, physical or mental, plausibly spans a lifetime. Probably there is no part of you that spans even a decade, maybe not even an hour. To accept this truth, it may help to know how such a profound mistake came about. It's quite natural: to bring about right action, it is instilled in children (brush your teeth now so you don't have cavities later), who naturally come to think of themselves as the protagonist in the story of their life. In adults it is reinforced by counsels of prudence (save for retirement) and sharing a world populated by people making the same mistake and acting accordingly. But the "I" is only a convenient designator, a mental crutch, and if we can throw it away while maintaining right action, we can rid ourselves of existential anxiety.
I think there is something to this view. It is hard to hold it in mind for long. So it seems plausible that a lot of special practice like meditation would be required to really live in it.
Some philosophers in the western tradition have arrived at similar ideas. Below are a few quotations/notes on the doctrine of non-self in relation to Hume, Parfit, and Kant.
Here is David Hume (cited by Siderits): "For my part, when I enter most intimately into what I call myself, I always stumble on some particular perception or other, of heat or cold, light or shade, love or hatred, pain or pleasure. I never can catch myself at any time without a perception, and never can observe any thing but the perception. When my perceptions are remov'd for any time, as by sound sleep; so long am I insensible of myself, and may truly be said not to exist. And were all my perceptions remov'd by death, and cou'd I neither think, nor feel, nor see, nor love, nor hate after the dissolution of my body, I shou'd be entirely annihilated, nor do I conceive what is farther requisite to make me a perfect non-entity. If any one, upon serious and unprejudic'd reflection thinks he has a different notion of himself, I must confess I can reason no longer with him. All I can allow him is, that he may be in the right as well as I, and that we are essentially different in this particular. He may, perhaps, perceive something simple and continu'd, which he calls himself; tho' I am certain there is no such principle in me."
And here is Derek Parfit (quoted by Siderits): "Is the truth depressing? Some may find it so. But I find it liberating, and consoling. When I believed that my existence was such a further fact, I seemed imprisoned in myself. My life seemed like a glass tunnel, through which I was moving faster every year, and at the end of which there was darkness. When I changed my view, the walls of my glass tunnel disappeared. I now live in the open air. There is still a difference between my life and the lives of other people. But the difference is less. Other people are closer. I am less concerned about the rest of my life, and more concerned about the lives of other people"
Finally, I have to call out an interesting twist on Kant. In his first critique, Kant argued that the concept of "I" implies an objective world. For Kant this was part of a modus ponens: we have the concept of "I", therefore there is an objective world. In the Yogacara tradition of Buddhism, Vasubandhu arrives at the same implication: the concept of "I" implies an objective world. But because Vasubandhu embraces the non-self, he wants the deduction to flow in the other direction, via modus tollens: [he argues on independent grounds] there is no objective world; therefore there is no "I". Beautiful.
(I am raising this book a full star because I keep referring back to it. It is good.)