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Understanding Beliefs

Understanding Beliefs

Copyright Date: 2014
Published by: MIT Press
Pages: 168
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  • Book Info
    Understanding Beliefs
    Book Description:

    Our beliefs constitute a large part of our knowledge of the world. We have beliefs about objects, about culture, about the past, and about the future. We have beliefs about other people, and we believe that they have beliefs as well. We use beliefs to predict, to explain, to create, to console, to entertain. Some of our beliefs we call theories, and we are extraordinarily creative at constructing them. Theories of quantum mechanics, evolution, and relativity are examples. But so are theories about astrology, alien abduction, guardian angels, and reincarnation. All are products (with varying degrees of credibility) of fertile minds trying to find explanations for observed phenomena. In this book, Nils Nilsson examines beliefs: what they do for us, how we come to hold them, and how to evaluate them. We should evaluate our beliefs carefully, Nilsson points out, because they influence so many of our actions and decisions. Some of our beliefs are more strongly held than others, but all should be considered tentative and changeable. Nilsson shows that beliefs can be quantified by probability, and he describes networks of beliefs in which the probabilities of some beliefs affect the probabilities of others. He argues that we can evaluate our beliefs by adapting some of the practices of the scientific method and by consulting expert opinion. And he warns us about "belief traps" -- holding onto beliefs that wouldn't survive critical evaluation. The best way to escape belief traps, he writes, is to expose our beliefs to the reasoned criticism of others.

    eISBN: 978-0-262-32112-9
    Subjects: Philosophy, Technology

Table of Contents

  1. Front Matter
    (pp. i-vi)
  2. Table of Contents
    (pp. vii-viii)
    (pp. ix-x)
    Bruce Tidor

    The MIT Press Essential Knowledge series offers accessible, concise, beautifully produced pocket-size books on topics of current interest. Written by leading thinkers, the books in this series deliver expert overviews of subjects that range from the cultural and the historical to the scientific and the technical.

    In today’s era of instant information gratification, we have ready access to opinions, rationalizations, and superficial descriptions. Much harder to come by is the foundational knowledge that informs a principled understanding of the world. Essential Knowledge books fill that need. Synthesizing specialized subject matter for nonspecialists and engaging critical topics through fundamentals, each of...

    (pp. xi-xiv)
    (pp. xv-xvi)
    (pp. 1-10)

    Our beliefs constitute a large part of our knowledge of the world. For example, I believe I exist on a planet that we call Earth and that I share it with billions of other people. I have beliefs about objects, such as automobiles, airplanes, computers, and various tools, and (to various degrees of detail) how they all operate. I have beliefs about the twenty-first-century culture in which I live: about democracy and the rule of law, about the Internet, and about science and the humanities, among other things. I have beliefs about many other people, including family, friends, associates, and...

    (pp. 11-20)

    Our beliefs serve us in several ways. Some help us make predictions and select actions, some help us understand a subject in more detail, some inspire creativity, some generate emotional responses, and some can even be self-fulfilling.

    First, let’s look at some of the ways people use beliefs to make predictions and select actions. In medicine, for example, physicians use their beliefs (learned in medical school and from journals, clinical studies, and on-the-job practice) to diagnose and predict the course of a disease and to prescribe a therapy predicted to cure or mitigate it. Corporate CEOs use their beliefs about...

    (pp. 21-34)

    Have you ever asked yourself, “Where did I get that belief?” or “Why do I believe that?” Sometimes we can give answers to such questions. “I saw it with my own eyes.” “I learned it in school.” “I read it in theWall Street Journal.”“I heard it on TV.” “My parents told me.” “I found it on the Internet.” Sometimes we aren’t sure and have to say something like, “I don’t know; it just seems right to me.”

    Interestingly, the anthropologist David Fleck describes a language spoken in Amazonian Peru and Brazil that requires “speakers to precisely and explicitly...

    (pp. 35-50)

    We hold some of our beliefs more strongly than others. If asked whether we believe such and such, we might answer by saying things like, “Yes, definitely, it’s a fact,” or “It’s quite likely to be so,” or “It’s possible,” or “It’s doubtful,” or “I don’t know,” or “Not at all.” These are some of the ways of describing degrees of belief. No one knows how our brains actually represent belief strengths. Perhaps we store some of them as sentences such as “I doubt that vitamin C can cure a cold.” Or, maybe our brains associate something like numbers with...

    (pp. 51-64)

    Many of our beliefs fall somewhere between the two extremes of “definitely false” and “definitely true.” Their position on that scale is indicated by what I have called a “strength.” To represent these strengths, we could use phrases, such as “almost certainly not,” “unlikely,” “possible,” “somewhat likely,” “likely,” “very likely,” or “virtually certain.” Or, we could use numbers between 0 (standing for definitely false) and 1 (standing for definitely true). It’s relatively easy to convert phrases about strength into numbers. For example, we might translate “virtually certain,” into 0.99 and “likely” into 0.7.

    Using numbers to represent strengths reminds us...

    (pp. 65-74)

    Our beliefs are descriptions ofreality. Some of them we even claim to betrue. What can be said about the subjects of reality and truth? Let’s discuss the subject of reality first. I believe that reality exists independently of our own thoughts and perceptions about it. The impact of reality on our senses (both natural and augmented senses) leads us to invent the concepts of various objects, properties, and relations, which we use in sentences to describe reality. One such sentence, for example, might be, “The San Andreas fault is a boundary between the Pacific and North American plates.”...

    (pp. 75-104)

    The set of practices scientists use to tease out descriptions of reality has come to be called “the scientific method.” As I have already mentioned, the scientific method is a highly disciplined, but still rather informal, application of the elements of critical thinking that many of us use quite naturally. In fact, Albert Einstein once said, “The whole of science is nothing more than a refinement of everyday thinking.”¹ These refinements consist mainly of careful observations followed by creating and testing explanations for these observations. People as far back as the Babylonians and ancient Greeks used many of these strategies...

    (pp. 105-116)

    Like humans, many robots and other computer systems are capable of complex behaviors, both physical and cognitive. On the physical side, for example, Google is developing automobiles that can drive themselves completely autonomously. According to a Google blog:¹

    Our automated cars, manned by trained operators, just drove from our Mountain View campus to our Santa Monica office and on to Hollywood Boulevard. They’ve driven down Lombard Street [which is very steep and curvy], crossed the Golden Gate bridge, navigated the Pacific Coast Highway, and even made it all the way around Lake Tahoe. All in all, our self-driving cars have...

    (pp. 117-130)

    I have stressed throughout this book that our beliefs should be subject to change. Scientists are used to having their theories replaced by better ones. Why shouldn’t we regard our everyday beliefs as tentative also? Even if we don’t replace a belief with a brand new one, we should be willing at least to change the strength of a belief based on new information and after discussions with others.

    While we may be intellectually willing to acceptin principlethat our beliefs should be tentative, it can be very difficult actually to change beliefs. It’s easy to get trapped with...

    (pp. 131-136)
  16. NOTES
    (pp. 137-142)
    (pp. 143-144)
  18. INDEX
    (pp. 145-151)