The Nature of Rationality

by Robert Nozick

Repeatedly and successfully, the celebrated Harvard philosopher Robert Nozick has reached out to a broad audience beyond the confines of his discipline, addressing ethical and social problems that matter to every thoughtful person. Here Nozick continues his search for the connections between philosophy and "ordinary" experience. In the lively and accessible style that his readers have come to expect, he offers a bold theory of rationality, the one characteristic deemed to fix humanity's "specialness." What are principles for? asks Nozick. We could act simply on whim, or maximize our self-interest and recommend that others do the same. As Nozick explores rationality of decision and rationality of belief, he shows how principles actually function in our day-to-day thinking and in our efforts to live peacefully and productively with each other.


Throughout, the book combines daring speculations with detailed investigations to portray the nature and status of rationality and the essential role that imagination plays in this singular human aptitude.

Genres: Philosophy, Nonfiction, Psychology, Economics

232 pages, Hardcover

First published January 1, 1993

About the author

Robert Nozick was an American philosopher and professor at Harvard University. He was educated at Columbia (A.B. 1959, summa cum laude), where he studied with Sidney Morgenbesser, at Princeton (Ph.D. 1963), and Oxford as a Fulbright Scholar. He was a prominent American political philosopher in the 1970s and 1980s. He did additional but less influential work in such subjects as decision theory and epistemology. His Anarchy, State, and Utopia (1974) was a libertarian answer to John Rawls's A Theory of Justice, published in 1971. He was born in Brooklyn, the son of a Jewish entrepreneur from Russia, and married the American poet Gjertrud Schnackenberg. Nozick died in 2002 after a prolonged struggle with cancer. His remains are interred at Mount Auburn Cemetery in Cambridge, Massachusetts.

Reviews

[Paul Gibson · Rating 4 out of 5]

I like a philosopher who can decide he was wrong about a major point he made publicly.
There was much to like in this book.

[A YOGAM · Rating 4 out of 5]

Wer verstehen will, warum wir denken, wie wir denken, findet hier eine außergewöhnliche Synthese aus Biologie und Entscheidungstheorie, die selbst Borel beim Kalkulieren von Wahrscheinlichkeiten noch einmal nach dem Bleistift hätte greifen lassen. Dieses Werk ist ein entscheidender Leitfaden gegen die strukturelle Überforderung des Denkens: Es zeigt, dass Rationalität weit mehr ist als ein kühles, zweckorientiertes Nutzenkalkül, sondern eine evolutionär gewachsene Fähigkeit, mit Unsicherheit, Zielkonflikten und begrenztem Wissen umzugehen.

[Gene · Rating 4 out of 5]

I bought this book twentyish years ago when I was reading a lot about decision theory. For some reason, I didn’t read it at the time. It’s been a while now since I’ve done anything with decision theory, so the book was a little more challenging than it would have been. But there is a lot to like in this book outside of the more technical passages. It’s a book that raises a lot of interesting questions that I’m sure I’ll be thinking about for some time.

[Dio Mavroyannis · Rating 5 out of 5]

I was very unsure if I should read this book, the introduction didn't compel me. But I quickly regretted my doubts. The first chapter touched on my own research topic and the rest of the book serves to explain in a very clear way the concept of Bayesian rationality, and belief structures. Overall a fantastic read, an overall more approachable text than others.

[Rick · Rating 4 out of 5]

Nozick uses quite a bit of science and higher level mathematics to explain the rationality and/or probability of propositions and beliefs. It makes the task of understanding very tedious.

[Edward · Rating 2 out of 5]

I recently took another look at this as I wanted to re-read Nozick's arguments for certain preferences being intrinsically irrational. Though this part was not very impressive upon rereading, other parts were nice to revisit. Some highlights:


"The word philosophy means the love of wisdom, but what philosophers really love is reasoning. They formulate theories and marshall reasons to support them, they consider objections and try to meet these, they construct arguments against other views. Even philosophers who proclaim the limitations of reason--the Greek skeptics, David Hume, doubters of the objectivity of science--all adduce reaons for their views and present difficulties for opposing ones" (The first paragraph).

"If rationality is an evolutionary adaptation with a delimited purpose and function, designed to work in conjunction with other stable facts that it takes for granted and builds upon, but if philosophy is an attempt of unlimited scope to apply reason and to justify rationally every belief and assumption, then we can understand why many of philosophy's traditional problems have turned out to be intractable and resistant to rational resolution" (xii).

If 2 beliefs are equally credible, pick the one that is more useful.

Since rationality can also help to identify group/personal bias, it’d be a shame if attacking reasoning took away that tool.

“The rationality of belief involves two aspects: support by reasons that make the belief credible, and generation by a process that reliably produces true belief” (xiv).

“For the intellectual heath of our society—not to mention the social health of our intellectuals—the fundamental ideas must stay public” (xvi).

“Principles are transmission devices for probability or support, which flow from data or cases, via the principle, to judgments and predictions about new observations or cases whose status otherwise is less known or uncertain” (5).

Legal principle stare decisis respects precedents so you can predict future decisions therefore can plan one’s behavior

“Justice, it is said, must not only be done, but be seen to be done” (11).

A person may define themselves by reference to their principles, and the principles give life a greater “coherence, greater organic unity. That may be valuable in itself” (13). Principles are lines one has drawn, limiting oneself, outer boundaries, therefore define a person. By saying what someone is not, it becomes more clear to see what they are.

“The political philosophy presented in Anarchy, State, and Utopia ignored the importance to us of joint and official serious symbolic statement and expression of our social ties and hence… is inadequate” (32).

(I skipped Ch. Of “decision value” as it was too technical)

“[Y:]ou more often arrive at a true belief if you hold your belief for supporting reasons. By giving reasons the major role, we make the processes that form our beliefs reliable” (67).

Rationality is being responsive to reasons

Maybe Pulitzers are such a big deal even if they are little money because they are about newspapers, and so newspapers make them a big deal. If you are making a small reward, tie it to news anchors and producers for more coverage!

“The philosopher’s attempt to ground reason is his effort to protect his love. (Or to ensure that his love stays true to him?)” (112).

Dawkins: “A chicken is an egg’s way to make another chicken” (128).

It is admirable and good to be rational “perhaps because so deciding and believing uses our high and intricate capacities and expresses them, or perhaps because that embodies an admirable and principled integrity in guiding beliefs and actions by reasons, not by the whims or desires of the moment” (136).

“It is symbolically important to us that not all of our activities are aimed at satisfying our given desires” (138).

Irrational preferences: the impossible (at least for the given person), lacking stable goals, if getting the desire met would make one irrational (like believing everything you are told, being with a liar without safeguards, choosing a state of continuous irrationality via booze, for example)

By exploring reasons for and against something, we are better exploring the thing’s nature

Rationality can give us the best of given available options, but, via imagination, can illuminate new options that are best of all

“Our principles fix what our lives stand for, our aims create the light our life is bathed in, and our rationality, both individual and coordinate, defines and symbolize the distance we have come from mere animality. It is by these means that our lives can come to mean more than what they instrumentally yield. And by meaning more, our lives yield more” (final paragraph).

[mk.miles_ · Rating 4 out of 5]

The Nature of Rationality is an incredibly interesting and underappreciated book. Having no real understanding of decision theory, I am probably not the best person to review it - but I did get a lot out of it.

Nozick covers a lot of ground in this work, but mostly discusses theories of utility and evolutionary explanations. He's trying to advance the idea of symbolic utility, suggesting that it ought to be considered in decision theory.

In my view, symbolic utility certainly has it's place. While it could, in theory, be subsumed by CEU and EEU, Nozick's SU is more immediately material, quickly explaining why people pursue goals that otherwise appear altruistic or ideological - pursuits which seem less self-interested, but in some more ultimate sense might actually be so.

[Simona · Rating 4 out of 5]

This was tough to read. It is my first serious reading on decision theory, so I was just familiarising myself with general ideas. I suspect that this is not the best choice for beginners, but at least it is NOT one of those popular science booka for general audience, those frustrate me :-) . Some nice ideas, I can never quite imagine the complexities thet could possibly arise from characterising words like: belief,reason, principle, goal, preference.