Wednesday, April 27, 2011

On Richard Feynman & The Philosophy of Science

After a series of posts on the topic of energy policy and economics, I thought that it'd be a good time to take a break and delve back into what got me interested in energy policy in the first place: Physics.
So,  I've pieced together some thoughts about the person who captivated me the most during college: Richard Feynman. It's crazy seeing interviews of him on YouTube. During college, all I had were his books. Way back in grad school, I found a few tapes of his lectures series in the school's library. I'm glad that somebody posted interviews with him online. More graduate program classes need to expose students to Feynman. His character shines through in any of these mediums.


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    Richard Feynman’s concept of science places physics as the backbone for all other sciences. In his view, all sciences are similar in the fact that the work in each field can be reduced to a set of laws. In the first three lectures from his Lectures on Physics, Feynman makes claims about the nature of science, such as: the laws, the nature of experimentation, the need for predicting, and the relationship between fields of science. Feynman gives insight into the basis for what is a science and what is not a science, but he is vague about how his views conform to or disagree with the the numerous philosophical theories about science. One problem I have with Richard Feynman is that he had virtually no respect for philosophy as a field of study. And so, while I highly respect Richard Feynman as a scientist and a teacher, I think that his view on philosophy is sort of skewed.
   With that having been said, reading the collection of works by Richard Feynman had by far and away the most impact on my decision to study physics in college and graduate school. His way of explaining physics was beautiful and simple. However, I often disagree with his philosophy of life, which I will summarize right now as:  "The goal of life is to discover the laws of the universe."
   The problem I wish to discuss in the post is the following: what is Feynman's justification for his philosophy of life? Is there any physical grounding for this philosophy of life? Is this a good philosophy of life to hold? And why did he have such low respect for philosophers who might not agree with Feynman's philosophy of life, and instead were interested in exploring the logical consequences of other philosophies of life?



        The following is a summary of some of the claims that Feynman makes about the laws of physics, using his own words as much as possible. And this summary will be used as a spring board for discussing the questions mentioned above.

[Claim #1—Reduction to Laws] 
   “It is possible to condense the enormous mass of results to a large extent—that is, to find laws which summarize all our knowledge” (1-1). It is particularly interesting that Feynman uses the word ‘find’ instead of other words, such as ‘discover’ or even ‘make.’ If he had used the word ‘make,’ then the suggestion would have been that all humans can do is to attempt to conform nature to our perception of it. But I think that Feynman's use of the word 'find' suggests that, in his mind, the laws of physics are independent of how, why or who discovers them. This is an interesting philosophical statement,  but the question remains: what is a physical law? Is it a mathematical equation or a verbal statement? Can a bear or a chipmunk learn the laws of physic?

[Claim #2—More Laws to Discover]    
    Feynman’s first claim also suggests that the laws describe how nature works anywhere in the Universe (not just on the third rock from the Sun). Yet, Feynman gives two reasons why his students can’t just learn the ‘laws’ of physics and deduce all further actions of nature. First, “We do not yet know all of the basic laws: there is an expanding frontier of ignorance” (1-1). It seems as though this is just a simple statement saying that the more we learn, the more we realize there is to learn. This once again reinforces Feynman's idea that the laws are ‘discovered’ because if they were ‘made,’ then this statement would be automatically assumed, i.e. the claim would not need to be mentioned. 

 [Claim #3—Mathematics as the Language to Understanding Physics]
  “The correct statement of the laws of the physics involves some very unfamiliar ideas which require advanced mathematics for their description. Therefore, one needs a considerable amount of preparatory even to what the words mean” (1-1). There is an interesting relationship between math and physics, one that he explores further in The Characteristics of Physical Laws. The above quote seems to imply that physics needs to be learned as a habit, and that language has a considerable amount to do with how one defines physics. An interesting question is whether we need mathematics to explain nature. The idea of the fallibility of our laws in describing nature appears in how the following claims might or might not suggest that everything known collectively to scientists is only a form of approximation, dependent on the tools they use to experiment. 

[Claim #4—Truth in Approximation]
Using a form of approximation, Feynman states, “A true law is: if an object moves with a speed of less than one hundred miles a second the mass is constant to within one part in a million. In some such approximate form this is a correct law” (1-2). It was assumed before Einstein that mass was a constant. Feynman seems to imply here that the results of experiments before Einstein weren’t wrong; they just couldn’t be used to calibrate below one part in a million. Feynman seems to prefer to stay away from these ‘true laws’ because do not reveal the true workings of nature, and they don’t require a scientist to stick his neck out. The first four claims show that his take of the nature of laws is important in understanding his taken on scientists’ abilities to model nature.


[Claim #5—Experimentation and Scientific Truth]
   Feynman’s discussion of experimentation and predicting shows that he believes that the scientific method will lead us to laws of nature that don’t need to be approximate. There are three major components of the scientific method for Feynman: observation, reason, and experiment. It is the last of these that he focuses on. “The principle of science, the definition, almost, is the following: The test of all knowledge is experiment. Experiment is the sole judge of scientific ‘truth’” (1-1). This statement seems to be aimed at the general public who might claim to act ‘scientifically’ when creating beliefs, but who might not actually run the experiments it takes to give justification to such a belief. It also can be seen as a critique of theoretical attempts to explain the world without ‘hands-on’ experimentation, when the subject matter allows. And I think that this is principally the problem that Feynman sees with philosophy as a sciece: the inability to experiment.

 [Claim #6—Science’s Need to Predict]
   For Feynman, the other important aspect of science is the ability to predict. “The basis of a science is its ability to predict. To predict means to tell what will happen in an experiment that has never been done” (38-9). This is where theory comes into the picture; theory can help tell a scientist which experiments are more crucial than others are. Since scientist don’t know where their laws are ‘incorrect,’ they have to make predictions and “stick [their] necks out.” The interesting areas are, for Feynman, where the laws break down. Feynman states his definition for predicting in more detail in a section on the philosophical implications of quantum mechanics, especially with respect to Heisenburg’s uncertainty principle.

 [Claim #7—Science does not equal Determinism]
    “Philosophers have said before that one of the fundamental requisites of science is that whenever you set up the same conditions, the same thing must happen. This is simply not true, it is not a fundamental condition of science” (38-8). Feynman's claim here is that science needs to predict does not necessitate that nature is deterministic. The problem is: how do you prove a probability? Predicting is a Popperian way of sticking ones neck out to see if the prediction is false. In Feynman's mind, this is a key feature of natural science, and not of “Cargo-cult sciences”[1] such as psychoanalysis. But how do you know your Bell Curve of results doesn't broaden or shift after the millionth experiment? Can one ever claim the absolute truth of a law if it based on a probability of expected results? (My own opinion, as you can guess from my comments later, is that it doesn't matter if a law is absolutely true or approximately true as long as the law can be used to predict nature to the degree needed to continue the expansion of life.)


[Claim #8—Understanding equals How not Why] 
   Feynman also spends an entire lecture dealing with the relationship between physics and other sciences. The attempt here is to highlight what he sees as a common thread within the sciences. Feynman uses a metaphor of an observer watching a chess game to describe the relationship between the scientist and the ‘world.’ This metaphor has undertones of the realist’s concept that a statement, a sentence or a law is true when there is a one-to-one correspondence with reality. “If we know the rules, we consider that we ‘understand’ the world… The rules of the game are what we mean by fundamental physics” (2-1). To continue upon Feynman's analogy, it seems as he thinks it is more important to know the laws of chess than it is to understand who wins or why one person beat another person at chess. Feynman is also vague about whether we can ever really know all of the rules, but it seems as though he believes this is possible. What is easy to see is his placement of physics with respect to the other sciences.

[Claim #9—Physics Precedes Chemistry & Biology]
The first science Feynman mentions is chemistry, yet Feynman mentions that theoretical chemistry is simply physics. He sees quantum physics as the backbone to all chemistry. In an even more bold statement, he says, “Everything is made of atoms. That is the key hypothesis. The most important hypothesis in all of biology, for example, is that everything that animals do, atoms do. In other words, there is nothing that living things do that can’t be understood from the point of view that they are made of atoms acting according to the laws of physics” (1-9). It seems than from this statement that biologists should be forever grateful to physics in telling them how to do their job as scientists. And here, I will be taking a contradicting view similar to Douglas Hofstadter ("Godel, Escher, Bach" & "I am a Strange Loop"). I think that the laws of non-equilibrium thermodynamics allow for 'dissipative structures' to appear that can effectively be treated as irreducible objects that move unpredictably, even though they obey the first and second laws of thermodynamics. And hence, I think that there is no way to reduce biology to physics because physics is the substrate and not the structure, i.e. there might be laws of biology that transcend the substrate and hence transcend the underlying physics. I mean: there might be laws of biology that might still be laws of biology if one or more of the underlying laws of physics were changed or removed.
  
[Claim #10—Psychoanalysis does not have falsifiable claims]
   Though, Feynman is a little bit more humble in stating that physics did initially grow out of astrophysics. Feynman mentions one field as not being a science. “Psychoanalysis is not a science: it is at best a medical process, and perhaps even more like witchdoctoring… [It] has not been checked carefully by experiment, and there is no way to find a list of cases in which it works, the number of cases in which it does not work, etc.” (3-8). I'm not sure what to think about Feynman's dislike of psychoanalysis. While it does seem to be impossible to falsify psychoanalysts’ theories (because they seem to be making ad hoc adjustments to fit all the possible cases into their theory), it might be possible to eventually apply Popper's rules of 'experimentation to attempt to falsify a theory' to the theories of psychoanalysis that predict a probability of a certain event to occur. Feynman mentions one field of interest that separates physics from all other sciences: the question of history. Physics does not ask how the atoms (etc.) got into the certain positions, but this is definitely a question that astrophysicists and biologists ask. Feynman avoids here any mention of ‘progress’ or a statement that nature herself is heading towards some deep state of meaning. Here is where I think that Feynman is afraid to 'stick his neck out.' If you only study the field of near-thermal equilibrium, then there is no 'history.' But the world is not close to equilibrium, and many of the equations of far-from-equilibrium physics have the variable 'time' show up other than just a differential 'dt', and hence if you want to study the physics of objects far-from-equilibrium, then you need to know the 'history' of the objects. History is a consequence of physics, and the only time that there will be no 'history' will be when/if the universe is in equilibrium.
The above paragraphs address the key aspects of Feynman's claims about the nature of science. What follows will be an analysis of Feynman’s claims about the nature of science. The first area of interest is falsification. The implication from the Popper-like claim #6 (Science’s need to Predict) is that scientists willingly go out to uncharted areas to attempt to falsify their theory, where predicting and experimentation equate with falsifying. This does not fit with Kuhn’s description of ‘normal science’ where scientists try to stay within the confines of a certain paradigm. [2] The scientist operating in 'normal science' mode, in Kuhn’s view, does not think about creating new laws. His job is not to attempt to falsify the paradigm. Feynman’s lectures are vague in describing what types of hypotheses scientist should attempt to falsify. One could read Feynman, in light of Kuhn’s Structures, as saying that a scientist working with a certain paradigm should create hypotheses that can be tested experimentally to attempt to falsify them. However, a statement like the one above is philosophically naïve given Duhem’s belief that we can’t falsify isolated hypothesis. Duhem's thesis is that the attempt to falsify through experimentation can never prove one hypothesis wrong, but rather would prove a group of hypotheses wrong. Since Feynman is so vague in this area of how to falsify, one can only comment that his claims in the first three lectures fail to give an accurate description of how science works in the laboratory setting.
Another area of thought where Feynman seems to have a weak conception of the nature of science is determining the ultimate relationship between language and ‘reality.’ Feynman discusses the role of language briefly claim #3 (Mathematics as the Language to understanding Physics). Yet, he fails to mention our dependence on language in describing the ‘world.’ The following is a statement of one of Kuhn’s major themes in Structures. “Each [scientific revolution] transformed the scientific imagination in ways that we shall ultimately need to describe as a transformation of the world within which scientific work was done” (15). Kuhn attempts to break away from the view that there is a reality out there for us to understand. In Kuhn’s view, the difference between the past and the present is that we ask different questions; the questions aren’t better, just different. This is definitely not the way that Feynman would view the nature of the world and the nature of science, based on claims #1 (Reduction to Laws) and #2 (More Laws to Discover). It appears that Feynman believes that a law, such as F=ma, is a ‘rule’ of how nature works, and not a human construct. The problem with believing such a statement is that the equation requires a lot of definitions. This equation is just one way of making nature conform to our language, a language that uses such words as force, mass, & acceleration. Do these words reveal the fundamental nature of ‘reality’? Years from now scientists might sit back and laugh at the fact that we used such words as 'mass,' just as we subtly mock the use of the word 'phlogiston.' There is a clear sense from reading Feynman that he believes that there actually is a reality in which physics is beginning to understand. So, returning to the idea of fallibility of our current laws, it seems as though Feynman is a 'anti-realist' in the sense that he sees our present laws as only approximate. Yet, he appears as a 'realist' in the sense that he believes that we can eventually find laws that do not need approximating.
Feynman presents a foundation in his first three lectures about how physics is the keystone for science, and how physics attempts to determine the rules/laws fundamental to the universe by using a scientific method that values experimentation and prediction. There are arguments throughout his lectures to support his idea (which many physicists share) that physics is the most important field of science. Do physicists really need to think that physics is the most important field in order to discover the fundamental laws of nature?
And I'd like to continue here with the question: is that philosophy of life (that the goal of life is to discover the laws of the universe) a good philosophy of life? It seems to me that this could be a rather poor philosophy of life if one takes it to the extreme and believes that those people who do not discover the laws of the universe of not of any value. For example, if the goal of life is to discover the laws of physics, what is the value to society of anybody not devoted to the goal of discovering these laws?
 So, while I highly respect Richard Feynman as a scientist and as a teacher of the equations of physics, I've often had problems with his philosophy that the most valuable thing in life is to discover the laws of physics and I've often had problems with his claims that physics is somehow independent of philosophy. And while I hold a different philosophy of life (that the goal of life is to expand and bring the universe into equilibrium), I am humble enough to recognize that my belief in this philosophy does not make me better than people who hold different philosophies of life. (For example, I am actively supporting and communicating the philosophy that the goal of life is to expand, but recognize that I am not better than people who have different views.) My problem with Richard Feynman (and with Richard Dawkins) is that they seem to have world views in which they are better than everybody else, and worse, that those people who aren't trying to discover the laws of physics (or aren't devout atheists) have no value. Instead, I think that the philosophy of life (that the goal of life is to expand) is more inclusive and capable of making everybody a valuable member of society, while recognizing that 'making' or 'discovering' the laws of physics is an important step towards expanding life to other planets.

In summary, studying physics should not be a means in itself, but rather studying physics should be a means to an end. The end is the expansion of life within the universe, and it's important not to value the 'means' (the laws) more than the 'ends' (life itself). I hope that reading this post will encourage you to figure out what you think about Feynman's ideas on physics by reading (or re-reading) his excellent Lectures on Physics.




[1] Feynman, Richard. Surely You’re Joking Mr. Feynman.
[2] Feynman’s lecture series does pre-date the release of Kuhn’s The Structures of Scientific Revolutions.

3 comments:

  1. This is such a great article. I agree the value is in life itself.

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  2. Well, we can simply agree to disagree. I do not share your philosophy, and I certainly don't think expanding our species in space ought to be our priority. Like Feynman, I'm much more interested in how the physical world behaves, and I do physics for the sake of it. I'm not trying to answer any "deep" questions about life, existence and all the other nonsense that is 'meta-physics'.

    "For example, if the goal of life is to discover the laws of physics, what is the value to society of anybody not devoted to the goal of discovering these laws?"

    There is no objective purpose/goal of life; it can be anything. For Feynman, me and other curious creatures, we just want to find out more about the universe, regardless of whether it benefits human-kind.

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  3. Anonymous,
    The statement "There is no objective purpose/goal of life; it can be anything." is a philosophical statement. It is a certain view of life, based off of your understanding of the data you see in front of you, which is based off of your brain's hardware that interprets the data you see in front of you. (A brain evolved to aid in the self-replication of life.)
    The problem is that, from your philosophical statement, there are a few logical consequences. First, if there is no purpose to life, how do we make laws and have a justice system? If there is no purpose to life, then is any action justifiable?
    Make sure that if you are going to make a philosophical statement about the purpose of life, then you are ready to defend the consequences of such a philosophy of life.
    I'd be glad to discuss this via comments on this post or via email.
    Best,
    Eddie

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