Krauss about Philosophy (2 of 2)

Posted on 2012/05/01


Feature Image - Krauss about Philosophy part 2

In the first part of this small analysis, I considered some comments on philosophy made by Lawrence Krauss; physicist and popularizer of science. It seemed that in a recent interview to promote his new book (‘A Universe from Nothing’), Krauss was suggesting that the only useful type of philosophy wasn’t really philosphy at all, but actually mathematics and logic.

This sort of sentiment is characteristic of many popularizers of science over the past few decades, and one that I think is quite incorrect.

After briefly sketching out the biography of Wittgenstein as a man who cared very little for scientific matters, I tried to indicate that he had, nevertheless, still produced some very valuable philosophy.

Next, i’d like to address Krauss’ comments about the use of philosophy for physicists.



In a recent syndicated article, Krauss attempted to redress concerns about his dismissive criticisms of philosophy. After some throat-clearing about how moral philosophy is very valuable, and how he read Plato as a young boy, we hear what Krauss thinks about the Philosophy of Science:

Krauss: What I find common and so stimulating about the philosophical efforts of these intellectual colleagues is the way they thoughtfully reflect on human knowledge, amassed from empirical explorations in areas ranging from science to history, to clarify issues that are relevant to making decisions about how to function more effectively and happily as an individual, and as a member of a society.

As a practicing physicist however, the situation is somewhat different. There, I, and most of the colleagues with whom I have discussed this matter, have found that philosophical speculations about physics and the nature of science are not particularly useful, and have had little or no impact upon progress in my field. Even in several areas associated with what one can rightfully call the philosophy of science I have found the reflections of physicists to be more useful. For example, on the nature of science and the scientific method, I have found the insights offered by scientists who have chosen to write concretely about their experience and reflections, from Jacob Bronowski, to Richard Feynman, to Francis Crick, to Werner Heisenberg, Albert Einstein, and Sir James Jeans, to have provided me with a better practical guide than the work of even the most significant philosophical writers of whom I am aware, such as Karl Popper and Thomas Kuhn. I admit that this could primarily reflect of my own philosophical limitations, but I suspect this experience is more common than not among my scientific colleagues.[1]

I think these statements are another symptom of Krauss’ philosophical myopia. He seems unable to see the contributions that philosophers make that lead up to a new physical theory.

For instance, it is well known that Albert Einstein was influenced by the philosophical work of David Hume and Ernst Mach. For example, in a letter to Moritz Schlick, Einstein writes:

Your exposition is also quite right that positivism suggested rel. theory, without requiring it. Also you have correctly seen that this line of thought was of great influence on my efforts and indeed E. Mach and still much more Hume, whose treatise on understanding I studied with eagerness and admiration shortly before finding relativity theory.[2]

Hume was by no means a physicist. And while he attempted to “extend to philosophy in general the methodological limitations of Newtonian physics”, there is no indication that Hume had any proficiency with the work of Newton.[3] Hume was a philosopher.

Years after Einstein wrote that letter, he expanded his theory to include gravitation. And, once again, he found Mach’s philosophy was vital to shaping his thoughts. In a Kyoto lecture of 1922, Einstein said (translated from the German):

Ernst Mach was a person who insisted on the idea that systems that have acceleration with respect to each other are equivalent. This idea contradicts Euclidean geometry, since in the frame of reference with acceleration Euclidean geometry cannot be applied. Describing the physical laws without reference to geometry is similar to describing our thought without words. We need words in order to express ourselves. What should we look for to describe our problem?


Concerning my work after 1915, I would like to mention only the problem of cosmology. This problem is related to the geometry of the universe and to time. The foundation of this problem comes from the boundary conditions of the general theory of relativity and the discussion of the problem of inertia by Mach. Although I did not exactly understand Mach’s idea about inertia, his influence on my thought was enormous.[4]

Anyone familar with the ‘Mach Number’ will know that Mach was indeed a physicist. Even so, his mathematical training was quite inadequate for him to comprehend the work of Einstein.

The philosopher and historian Gerald Horton has suggested that Mach was perhaps mislead by non-mathematical accounts of relativity, noting that, “…Ernst Mach knew and confessed he had only a rather elementary knowledge of mathematics.”[5] He initially supposed that Einstein agreed with him on more than was actually the case. Later, when it became obvious that Einstein’s General Relativity was a departure from Mach’s original philosophy, he felt obliged distance himself from it.

In a controversial posthumous publication, Mach wrote:

I am compelled, in what may be my last opportunity, to cancel my views of the relativity theory. I gather from the publications which have reached me, and especially from my correspondence, that I am gradually becoming regarded as the forerunner of relativity. I am able even now to picture approximately what new expositions and interpretations many of the ideas expressed in my book on Mechanics will receive in the future from this point of view. (…) I must, however, as assuredly disclaim to be a forerunner of the relativists as aI personally reject the atomistic doctrine of the present-day school, or church.[6]

Yet, the contribution of Mach’s writing for Einstein should not be underestimated.

John Norton, in the abstract to his paper ‘How Hume and Mach Helped Einstein Find Special Relativity’, writes:

He was aided decisively not by any specific doctrine of space and time, but by a general account of concepts that Einstein found in Hume and Mach’s writings. That account required that concepts, used to represent the physical, must be properly grounded in experience. In so far as they extended beyond that grounding, they were fictional and to be abjured (Mach) or at best tolerated (Hume). Einstein drew a different moral. These fictional concepts revealed an arbitrariness in our physical theorizing and may still be introduced through freely chosen definitions, as long as these definitions do not commit us to false presumptions. After years of failed efforts to conform electrodynamics to the principle of relativity and with his frustration mounting, Einstein applied this account to the concept of simultaneity. The resulting definition of simultaneity provided the reconceptualization that solved the problem in electrodynamics and led directly to the special theory of relativity.[7]

In reshaping the physics of mechanics and gravitation, Einstein chose different assumptions for the ‘arbitrary fictions’ of simultaneity and 3D space. Yet, he could only modify these assumptions once he had the insight to recognize them. And that insight was philosophical.



[2] Letter from Einstein to Moritz Schlick December 14, 1915

Available in:

Schulmann, Robert; Kox, A. J.; Janssen, Michel and Illy, József (eds.) (1998) ‘The Collected
Papers of Albert Einstein. Volume 8. The Berlin Years: Correspondence, 1914-1918.
Part A: 1914-1917′ Princeton: Princeton Univ. Press. [Doc. 165]

[3] Copplestone, F (2003) ’A history of Philosophy‘ v. 6

[4] Einstein, A (1922) ‘How I Created The Theory of Relativity‘ [Appears in 'Physics Today' August 1982 pp 45-47. Translation by Yoshimasa A. Ono of a 1922 Kyoto lecture by Einstein]

[5] Horton, Gerald (1993) ‘Science and Anti-Science‘ p 61

[6] E Mach (1926) ‘The Principles of Physical Optics‘ (New York: Dover Publications) pp vii-viii

[7] Norton, John (2004) ‘How Hume and Mach Helped Einstein Find Special Relativity‘ (Department of History and Philosophy of Science, University of Pittsburgh)

Posted in: Book Review