Coursera – Philosophy and the Sciences

I just finished to follow Coursera’s course Philosophy and the Sciences by Prof. M. Massimi and collaborators (from the University of Edinburgh). They already presented an Introduction to Philosophy which was very interesting. This course was split in two parts, one on cosmology and another on cognition. While the latter was rich and contained many interesting thoughts – on embodied cognition, evolutionary psychology and the nature of the mind –, the second was quite disappointing, mainly because it was not accurate and was proponent of the theory of the multiverse as the « best » solution to the value of the cosmological constant (and to other problems). The argument does as the following: all possible universes with all possible values of parameters exist, and we happen to be in the one that allows our existence – end of the story. I will just quote the conclusion of [1] which expresses perfectly my feeling: “Personally I feel the urge to wash my hands after having been in touch with these kinds of arguments. I prefer my principles trivially true.”

The course starts with a general introduction (from M. Massimi) to the philosophy of science, with the classical presentation of Kuhn and Popper theories. This is interesting for having the general ideas in a nutshell. In particular are presented the concepts of paradigm shift, refutability, underdetermination of theory by observations, etc.

Then the lectures go on with cosmology and the problems of dark matter, dark energy and associated problems of cosmology (horizon problem…), after having presented the basic ideas of cosmology. Until this point the lecture of J. Peacock is fine, but I did not like the following. Many statements are given without a clear delimitation between what comes from proven theories and what are just hypothesis, nor for which statement implies which other. For example multiverse is given as a necessary consequence of inflation (which is basically the case for eternal inflation, but not a generic feature of inflation itself), string theory is given as a necessary element for inflationary multiverse. At the end an argument by S. Weinberg is given as if it was proved, and finally it is said that inflation can be proven (by finding primordial gravitational waves), which would prove everything else as if it was a package – but this is wrong. This view is also supported by the way questions are asked in quizzes. I would say that for someone who does not know the topic this presentation is unclear and very dangerous. Note also that some chauvinism is present as only Higgs is cited for the discovery of the « Higgs » mechanism, and no one from Brout or Englert (or Hagen, Guralnik and Kibble), which is quite surprising since philosophers tends to give all due credit usually (but let’s mention that Higgs is in Edinburgh…).

I should mention that one of the lecture on cosmology was done by A. Richmond, who explained the anthropic principle – saying that the fact we are existing (and the galaxies, etc.) is correlated to the values of the parameters of our theories –, and this was an good lecture (except for the conclusion which comes back to the multiverse). It is clearly explained that the anthropic principle is not a tautology, but it is merely a tool to get constraints on the parameters, such as the cosmological constant. But not that if one gets the values this is not an explanation (i.e. there is no causation). I will refer to [1] for more details on this kind of reasoning.

The second part was quite simple but contained interesting materials. I already spoke about evolutionary psychology earlier, and the major idea I will take from this course is the notion of embodied cognition. The point is that the brain and the body co-evolved and it does make necessarily sense to really split them in two independent systems – or at least seeing the brain as the king, sufficient by itself, as is popular in modern neurosciences. Indeed it appears that many functions can be done by the body without action from the brain, and this is helpful since the brain is not overwhelmed by trivial computations. For example walking is very natural when considering the way legs are designed, and it is possible to get robots without brain (called passive dynamics walkers) having a much more natural walk than « advanced » robot with a brain, see for example [2].

Another problematic point of this course concerns the forum. It is almost not watched by professors or teaching assistants, and there are many crackpots (persons having no ideas of modern science and proposing wild theories on anything), and most of the answers given to questions are wrong. I would not recommend a course where the teachers do not ensure that students are not exiting with wrong beliefs. This is even worse since participating on the forum is mandatory (few points are given).

At the end this course was not very demanding such that it is worth to follow it: there was two essays, and a quizz for each week; it is even possible to validate it by following only one part. Hence I would advise to take a look at the second part, and at the beginning of the first one.

Bibliography

  1. 10 things you didn’t know about the Anthropic Principle, Prof. S. Hossenfelder, blog Backreaction.
  2. A Tale of Two Robots, Psychology Today.

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