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The Logical Leap: Induction In Physics
FrederickSeiler writes "When David Harriman, this book's author, was studying physics at Berkeley, he
noticed an interesting contrast: 'In my physics lab course, I learned how to determine the
atomic structure of crystals by means of x-ray diffraction and how to identify
subatomic particles by analyzing bubble-chamber photographs. In
my philosophy of science course, on the other hand, I was taught by a
world-renowned professor (Paul Feyerabend)
that there is no such thing as scientific method and that physicists have no
better claim to knowledge than voodoo priests.
I knew little about epistemology [the philosophy of
knowledge] at the time, but I could not help noticing that it was the
physicists, not the voodoo priests, who had made possible the life-promoting
technology we enjoy today.' Harriman noticed the enormous gulf between science as it is successfully
practiced and science as is it described by post-Kantian philosophers such as Feyerabend,
who are totally unable to explain the spectacular achievements of modern
science." Read on for the rest of Frederick's review.
The Logical Leap: Induction In Physics
author
David Harriman
pages
272
publisher
NAL Trade
rating
9/10
reviewer
Frederick Seiler
ISBN
0451230051
summary
Explains how scientists discover the laws of nature
Logical Leap: Induction in Physics
attempts to bridge this gap between philosophy
and science by providing a philosophical explanation of how scientists actually
discover things. A physicist and physics teacher by trade, he worked with
philosopher Leonard Peikoff to understand the process
of induction in physics, and this book is a result of their collaboration.
Induction is one of the two types of logical argument; the other type is deduction. First described by Aristotle, deduction covers arguments like the following: (1) All men are mortal. (2) Socrates is a man. (3) Therefore, Socrates is mortal. Deductive arguments start with generalizations ("All men are mortal.") and apply them to specific instances ("Socrates"). Deductive logic is well understood, but it relies on the truth of the generalizations in order to yield true conclusions.
So how do we make the correct generalizations? This is the subject of the other branch of logic induction and it is obviously much more difficult than deduction. How can we ever be justified in reasoning from a limited number of observations to a sweeping statement that refers to an unlimited number of objects? In answering this question Harriman presents an original theory of induction, and he shows how it is supported by key developments in the history of physics.
The first chapter presents the philosophical foundations of the theory, which builds directly on the theory of concepts developed by Ayn Rand. Unfortunately for the general reader, Harriman assumes familiarity with Rand's theory of knowledge, including her views of concepts as open-ended, knowledge as hierarchical, certainty as contextual, perceptions as self-evident, and arbitrary ideas as invalid. Those unfamiliar with these ideas may find this section to be confusing. But the good news is that those readers can then proceed to the following chapters, which flesh out the theory and show how it applies to key developments in the history of physics (and the related fields of astronomy and chemistry). These chapters do a wonderful job at bringing together the physics and the philosophy, clarifying both in the process.
Harriman argues that as concepts form a hierarchy, generalizations form a hierarchy as well; more abstract generalizations rest on simpler, more direct ones, relying ultimately on a rock-solid base of "first-level" generalizations which are directly, perceptually obvious, such as the toddler's grasp of the fact that "pushed balls roll." First-level generalizations are formed from our direct experiences, in which the open-ended nature of concepts leads to generalizations. Higher-level generalizations are formed based on lower-level ones, using Mill's Methods of Agreement and Difference to identify causal connections, while taking into account the entirety of one's context of knowledge.
Ayn Rand held that because of the hierarchical nature of our knowledge, it is possible to take any valid idea (no matter how advanced), and identify its hierarchical roots, i.e. the more primitive, lower-level ideas on which it rests, tracing these ideas all the way back to directly observable phenomena. Rand used the word "reduction" to refer to this process. In a particularly interesting discussion, Harriman shows how the process of reduction can be applied to the idea that "light travels in straight lines," identifying such earlier ideas as the concept "shadow" and finally the first-level generalization "walls resist hammering hands."
Harriman's discussion of the experimental method starts with a description of Galileo's experiments with pendulums. Galileo initially noticed that the period of a pendulum's swing seems to be the same for different swing amplitudes, so he decided to accurately measure this time period to see if it is really true. Concluding that the period is indeed constant, he then did further experiments. He selectively varied the weight and material of the pendulum's bob, and the length of the pendulum. This led him to the discovery that a pendulum's length is proportional to the square of its period. Harriman notes the experiments that Galileo did not perform: 'He saw no need to vary every known property of the pendulum and look for a possible effect on the period. For example, he did not systematically vary the color, temperature, or smell of the pendulum bob; he did not investigate whether it made a difference if the pendulum arm is made of cotton twine or silk thread. Based on everyday observation, he had a vast pre-scientific context of knowledge that was sufficient to eliminate such factors as irrelevant. To call such knowledge "pre-scientific" is not to cast doubt on its objectivity; such lower-level generalizations are acquired by the implicit use of the same methods that the scientist uses deliberately and systematically, and they are equally valid.' One powerful tool for avoiding nonproductive speculations in science is Ayn Rand's concept of the arbitrary, and Harriman brilliantly clarifies this idea in the section on Newton's optical experiments. An arbitrary idea is one for which there is no evidence; it is an idea put forth based solely on whim or faith. Rand held that an arbitrary idea cannot be valid even as a possibility; in order to say "it is possible," one needs to have evidence (which can consist of either direct observations or reasoning based on observations).
Newton began his research on colors with a wide range of observations, which led him to his famous and brilliant experiments with prisms. Harriman presents the chain of reasoning and experimentation which led Newton to conclude that white light consists of a mixture of all of the colors, which are separated by refraction.
Isaac Newton said that he "framed no hypotheses," and here he was referring to his rejection of the arbitrary. When Descartes claimed without any evidence that light consists of rotating particles with the speed of rotation determining the color; and when Robert Hooke claimed without any evidence that white light consists of a symmetrical wave pulse, which results in colors when the wave becomes distorted; these ideas were totally arbitrary, and they deserved to be thrown out without further consideration: "Newton understood that to accept an arbitrary idea even as a mere possibility that merits consideration undercuts all of one's knowledge. It is impossible to establish any truth if one regards as valid the procedure of manufacturing contrary 'possibilities' out of thin air." This rejection of the arbitrary may be expressed in a positive form: Scientists should be focused on reality, and only on reality.
After discussing the rise of experimentation in physics, Harriman turns to the Copernican revolution, the astronomical discoveries of Galileo and Kepler, and the grand synthesis of Newton's laws of motion and of universal gravitation. But this reviewer found the most historically interesting chapter to be the one about the atomic theory of matter; this chapter is a cautionary tale about the lack of objective standards for evaluating theories. This story then leads to Harriman proposing a set of specific criteria of proof for scientific theories.
The final, concluding chapter addresses several broader issues, including why mathematics is fundamental to the science of physics, how the science of philosophy is different than physics, and finally, how modern physics has gone down the wrong path due to the lack of a proper theory of induction.
So, with the publication of Logical Leap, has the age-old "problem of induction" now been solved? On this issue, the reader must judge for himself. What is clear to this reviewer is that Harriman has presented an insightful, thought-provoking and powerful new theory about how scientists discover the laws of nature.
You can purchase The Logical Leap: Induction In Physics from amazon.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
Induction is one of the two types of logical argument; the other type is deduction. First described by Aristotle, deduction covers arguments like the following: (1) All men are mortal. (2) Socrates is a man. (3) Therefore, Socrates is mortal. Deductive arguments start with generalizations ("All men are mortal.") and apply them to specific instances ("Socrates"). Deductive logic is well understood, but it relies on the truth of the generalizations in order to yield true conclusions.
So how do we make the correct generalizations? This is the subject of the other branch of logic induction and it is obviously much more difficult than deduction. How can we ever be justified in reasoning from a limited number of observations to a sweeping statement that refers to an unlimited number of objects? In answering this question Harriman presents an original theory of induction, and he shows how it is supported by key developments in the history of physics.
The first chapter presents the philosophical foundations of the theory, which builds directly on the theory of concepts developed by Ayn Rand. Unfortunately for the general reader, Harriman assumes familiarity with Rand's theory of knowledge, including her views of concepts as open-ended, knowledge as hierarchical, certainty as contextual, perceptions as self-evident, and arbitrary ideas as invalid. Those unfamiliar with these ideas may find this section to be confusing. But the good news is that those readers can then proceed to the following chapters, which flesh out the theory and show how it applies to key developments in the history of physics (and the related fields of astronomy and chemistry). These chapters do a wonderful job at bringing together the physics and the philosophy, clarifying both in the process.
Harriman argues that as concepts form a hierarchy, generalizations form a hierarchy as well; more abstract generalizations rest on simpler, more direct ones, relying ultimately on a rock-solid base of "first-level" generalizations which are directly, perceptually obvious, such as the toddler's grasp of the fact that "pushed balls roll." First-level generalizations are formed from our direct experiences, in which the open-ended nature of concepts leads to generalizations. Higher-level generalizations are formed based on lower-level ones, using Mill's Methods of Agreement and Difference to identify causal connections, while taking into account the entirety of one's context of knowledge.
Ayn Rand held that because of the hierarchical nature of our knowledge, it is possible to take any valid idea (no matter how advanced), and identify its hierarchical roots, i.e. the more primitive, lower-level ideas on which it rests, tracing these ideas all the way back to directly observable phenomena. Rand used the word "reduction" to refer to this process. In a particularly interesting discussion, Harriman shows how the process of reduction can be applied to the idea that "light travels in straight lines," identifying such earlier ideas as the concept "shadow" and finally the first-level generalization "walls resist hammering hands."
Harriman's discussion of the experimental method starts with a description of Galileo's experiments with pendulums. Galileo initially noticed that the period of a pendulum's swing seems to be the same for different swing amplitudes, so he decided to accurately measure this time period to see if it is really true. Concluding that the period is indeed constant, he then did further experiments. He selectively varied the weight and material of the pendulum's bob, and the length of the pendulum. This led him to the discovery that a pendulum's length is proportional to the square of its period. Harriman notes the experiments that Galileo did not perform: 'He saw no need to vary every known property of the pendulum and look for a possible effect on the period. For example, he did not systematically vary the color, temperature, or smell of the pendulum bob; he did not investigate whether it made a difference if the pendulum arm is made of cotton twine or silk thread. Based on everyday observation, he had a vast pre-scientific context of knowledge that was sufficient to eliminate such factors as irrelevant. To call such knowledge "pre-scientific" is not to cast doubt on its objectivity; such lower-level generalizations are acquired by the implicit use of the same methods that the scientist uses deliberately and systematically, and they are equally valid.' One powerful tool for avoiding nonproductive speculations in science is Ayn Rand's concept of the arbitrary, and Harriman brilliantly clarifies this idea in the section on Newton's optical experiments. An arbitrary idea is one for which there is no evidence; it is an idea put forth based solely on whim or faith. Rand held that an arbitrary idea cannot be valid even as a possibility; in order to say "it is possible," one needs to have evidence (which can consist of either direct observations or reasoning based on observations).
Newton began his research on colors with a wide range of observations, which led him to his famous and brilliant experiments with prisms. Harriman presents the chain of reasoning and experimentation which led Newton to conclude that white light consists of a mixture of all of the colors, which are separated by refraction.
Isaac Newton said that he "framed no hypotheses," and here he was referring to his rejection of the arbitrary. When Descartes claimed without any evidence that light consists of rotating particles with the speed of rotation determining the color; and when Robert Hooke claimed without any evidence that white light consists of a symmetrical wave pulse, which results in colors when the wave becomes distorted; these ideas were totally arbitrary, and they deserved to be thrown out without further consideration: "Newton understood that to accept an arbitrary idea even as a mere possibility that merits consideration undercuts all of one's knowledge. It is impossible to establish any truth if one regards as valid the procedure of manufacturing contrary 'possibilities' out of thin air." This rejection of the arbitrary may be expressed in a positive form: Scientists should be focused on reality, and only on reality.
After discussing the rise of experimentation in physics, Harriman turns to the Copernican revolution, the astronomical discoveries of Galileo and Kepler, and the grand synthesis of Newton's laws of motion and of universal gravitation. But this reviewer found the most historically interesting chapter to be the one about the atomic theory of matter; this chapter is a cautionary tale about the lack of objective standards for evaluating theories. This story then leads to Harriman proposing a set of specific criteria of proof for scientific theories.
The final, concluding chapter addresses several broader issues, including why mathematics is fundamental to the science of physics, how the science of philosophy is different than physics, and finally, how modern physics has gone down the wrong path due to the lack of a proper theory of induction.
So, with the publication of Logical Leap, has the age-old "problem of induction" now been solved? On this issue, the reader must judge for himself. What is clear to this reviewer is that Harriman has presented an insightful, thought-provoking and powerful new theory about how scientists discover the laws of nature.
You can purchase The Logical Leap: Induction In Physics from amazon.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
While the greek word philosophia literally means "friend of wisdom", the common-day philosopher tends to stare at their naval and wonder if they even exist more than they use anything which might resemble wisdom.
Meanwhile, the engineer is creating ways to save lives, feed millions, and travel to Mars.
I - personally - find it frustrating that we listen to the naval-staring philosopher, and forget what wisdom is in the same moment.
The first chapter presents the philosophical foundations of the theory, which builds directly on the theory of concepts developed by Ayn Rand. Unfortunately for the general reader, Harriman assumes familiarity with Rand's theory of knowledge, including her views of concepts as open-ended, knowledge as hierarchical, certainty as contextual, perceptions as self-evident, and arbitrary ideas as invalid. Those unfamiliar with these ideas may find this section to be confusing.
"Ayn Rand" and "philosophical foundations" should not be in the same sentence. If you like something Ayn Rand says, then I guarantee you can find another philosopher said it only in a far more intellectually rigorous manner.
If only statements like this were problems of only philosophers. The real problem is that scientists are losing the sense of rigor in method as well.
The only litmus test for scientific method left nowadays is if you pass the review of your peers, that is couple of your colleagues from the same grant hunting boat.
I do not believe in karma. "Funny"=-6. Do good and forbid evil. Yours, Oft-Offtopic Flamebaiting Troll.
I recall the quote "Philosophy of science is about as useful to scientists as ornitology is to birds" being attributed to feynman. And i find it all too fitting for any discussion that tries to mix science and philosophy.
I have an inherent distrust of anyone that is basing inductive logic on the underpinnings of Ayn Rand's Objectivism, for the simple reason that I've never . . . *ever* . . . heard of Objectivism as being contributory to *any* philosophy of logic.
Quite the opposite in fact, I've seen logicians use her as examples of how people can be fooled by pseudo-logic which hides implicit assumptions under carefully concealed vagueness and frame shifting.
This smells more like an attempt to rehabilitate Ayn Rand as a genuine philosophical contribution than a book on logic.
Pug
An Invisible Entity of Vast Power whose existence must be taken on faith alone: Liberal Media
Scientist: "I cannot do much, but I can bake you a reasonably tasty fruitcake if you want?"
Philosopher: "No, I want God."
Emotions! In your brain!
But I guess my central point is that objectivism (which includes the laissez-faire botch) is at odds with her other big meme, enlightened self-interest, which requires doing good unto others and expecting it to benefit you.
Laissez-faire is a license to defraud. Human lives are finite, and the ability of a laissez-faire system to return one's evils back to oneself in time for them to overwhelm one's ill-gotten wealth is, evidently, minimal. If the system had a shorter feedback loop, or we lived long enough to be brought low by the results from this system, then laissez-faire would result in a competitive balance (albeit a tense one).
Given the subject of this book, and how Rand is the basis for much of it, you'd think she'd have understood that believing in laissez-faire was, if not arbitrary, then certainly not supported by the evidence. It's certainly true that all the evidence today points to the fact that loosening the brakes on wealth-accumulation is resulting in more pain for the human race overall and less for those who already got theirs. She even had a word for the sort of selfishness that dominates laissez-faire: "unenlightened self-interst". Blows my mind that she cocked it up that bad and promoted objectivism instead of pointing flashing neon arrows at it and saying "DON'T DO THIS".
Time to put the "enlightened self-interest" politics to work, and make sure people can distinguish them from the "unenlightened self-interest" practices that politics has been swinging towards for the past 30 years.
There are two novels that can change a bookish fourteen-year old’s life: The Lord of the Rings and Atlas Shrugged. One is a childish fantasy that often engenders a lifelong obsession with its unbelievable heroes, leading to an emotionally stunted, socially crippled adulthood, unable to deal with the real world. The other, of course, involves orcs. -- Kung Fu Monkey
This reminds me of a comic about an engineer at a philosopher conference.
All the so-called great philosophy questions can be answered definitively if you allow for the terms to be properly defined. The profession of the philosopher is to refuse adequate definition to these questions, so that they are unanswerable by design; their work is no better or more useful than religions assertions.
It does deal with "how confident are we that ______ can be used as a reliable model of reality?" On which point we have Bayes' Theorem and various less-than-precise fuzzy analogues such as the rubric we call "the scientific method."
So for those philosophers who worry about some sort of Ultimate Certainty Regarding Truth, I sometimes play the game but am not, in the end, worrying about whether it is Really True that my hands are typing on black keys with white lettering right now -- which is about the level you have to go to before "witch doctor truth" gets competitive with "quantum physics truth" for my attention.
Lacking <sarcasm> tags,
The problem with books like this -- even by physicists -- is that they all too rarely study the right things physicists have done. Induction/inference in epistemology is put on a mathematically sound axiom-based foundation by Richard Cox and E. T. Jaynes. The former wrote a truly marvellous monograph entitled "The Algebra of Probable Inference" (readily available on Amazon). E. T. Jaynes arrived at a very similar result following instead from Shannon's Information Theory (which is a consequence of Cox's prior work, although this is not generally recognized) and later enthusiastically adopted Cox's axioms as the basis for his own opus major "Probability Theory, the Logic of Science". Both are available as a twofer on Amazon (or even as part of a threefer with Sivia's work on Bayesian Analysis).
They have one enormous redeeming value -- they don't refer to any work on philosophy including any by Ayn Rand. These are serious works on mathematics, logic, probability theory, and science, and they contain algebra, not handwaving. Absolutely amazing algebra, by the way. The sum total of philosophy in Cox is his highly restrained observation that his work seems to have solved Hume's basic problem -- deriving the theory of inference so it is on a sound mathematical footing.
Two other places where this general topic is reviewed: David Mackay's superb: "Information Theory, Pattern Recognition and Neural Networks" where he explores the consequences of Shannon's Theorem in cryptography and data compression and reliable storage, then moves on to argue quite persuasively that the human brain and neural networks in general function as a Bayesian inference engine; and my own book-in-writing "Axioms".
rgb
Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
Yeah, but those guys are all unemployed, and it's reproducible that they're unemployed, so scientifically speaking it's a bad idea to go down that path. Or not, because it kant be proven.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
The only litmus test for scientific method left nowadays is if you pass the review of your peers, that is couple of your colleagues from the same grant hunting boat.
That's nonsense. Peer review is not about proving something is correct, and no scientist interprets it that way. Peer review is primarily about checking that your papers are clearly written and describe your work well enough that other people can understand what you did. It also has a secondary function of helping journals pick the articles their readers are most likely to be interested in (and down the road, most likely to cite). The real test of your work is in other scientists' response to it. And that can take a long time to sort out - years or even decades. Science works slowly, but so what? Speed isn't the goal. The goal is to work out the right answer, however long that takes.
"I'm too busy to research this and form an educated opinion, but I do have time to tell everyone my uninformed opinion."
Besides, ancient doctrines and "primitive" myths appear strange and nonsensical only because the information they contain is not known, or is distorted by philologists or anthropologists unfamiliar with the simplest physical, medial or astronomical knowledge. Voodoo, Dr Hesse's pièce de resistance, is a case in point. Nobody knows it, everybody uses it as a paradigm of backwardness of confusion. And yet Voodoo has a firm though still not sufficiently understood material basis, and a study of its manifestations can be used to enrich, and perhaps even to revise, our knowledge of physiology. [Against Method, pp. 35-36]
Feyerabend thinks that science and myth are very similar and are of comparable worth. (And note I said comparable, not "equal"; the point is that there are arguments about values that can be had in this regard.)
Are you adequate?