Philosophy limits the disputable sphere of natural science

Does this refer to the demarcation problem (what is natural science) or occam's razor (what is the best explanation)? Or is it meant ironically (there is no limit to the "sphere of natural science")? Or is he referring to some other philosophical idea? Or is he just riffing to get to his conclusion?

At a guess, it depends on which of these really adds "clarity" to thoughts. It's been so long that I read that book that I don't know whether, for Wittgenstein, the true propositions of the natural sciences are "thoughts". If so, then it seems at least possible that philosophy can "clarify" those propositions by simplifying and rejecting all extraneous propositions: elevating occam's razor to make it the only principle of philosophy. Though it seems strange to say we "cannot speak" of what propositions that are unnecessarily complex, even if this may be in the spirit of that book.

  • Wittgenstein is not one for irony:""The totality of true propositions is the whole of natural science", there is nothing left to philosophy there. With this in mind, 4.113 is explained by the surrounding quotes:"A philosophical work consists essentially of elucidations... It should limit the unthinkable from within through the thinkable", and goes well with 5.62 "the limits of my language are the limits of my world".
    – Conifold
    Commented Apr 18, 2019 at 19:11
  • so he's not referring to anything at all, it's just a step on the way to his conclusion? @Conifold
    – user38026
    Commented Apr 18, 2019 at 19:11
  • i think it's just as much in the spirit of the book to say that science should be simplified as to say that "there is nothing left to philosophy". obviously you're free to your opinion @Conifold
    – user38026
    Commented Apr 18, 2019 at 19:16
  • 1
    Certainly not to the "demarcation problem", which does not even emerge until a decade later and was of significance mostly to Popper et al., or Harman's inferences to the "best explanation" from 1965. The "mystical" interpretations relating "cryptic" quotes to Schopenhauer are also dismissed by most scholars. There is nothing left to philosophy as far as true propositions, simplification, or rather "elucidation", is exactly what Wittgenstein consigns to philosophy. And please, no more replies.
    – Conifold
    Commented Apr 18, 2019 at 19:21
  • if you don't want me to comment then be more direct in your comments (which are useful) @Conifold ? e.g. i don't see how you infer i'm wrong (about occam's razor) from your penultimate sentence above. i suppose that you take it all to be nonsense that is only has relevance to philosophy (not natural science). hm
    – user38026
    Commented Apr 18, 2019 at 20:10

1 Answer 1


The so-called Demarcation Problem is a little bit later, emerging with Vienna Circle and Popper.

But its origins are in the Tractatus :

4.03 A proposition communicates a situation to us, and so it must be essentially connected with the situation.

Thus, a true proposition is the picture of a fact.

4.05 Reality is compared with propositions.

4.06 A proposition can be true or false only in virtue of being a picture of reality.

Thus, empirical (or natural) science deals with facts (pieces of the world) and its propositions must agree with facts.

4.11 The totality of true propositions is the whole of natural science (or the whole corpus of the natural sciences).

4.111 Philosophy is not one of the natural sciences. (The word ‘philosophy’ must mean something whose place is above or below the natural sciences, not beside them.)

4.112 Philosophy aims at the logical clarification of thoughts. Philosophy is not a body of doctrine but an activity.

This is the core of Wittgenstein's view about philosophy : either philosophy is metaphysical (to be rejected as nonsense), or it is an activity of "elucidation" (mainly regarding the use of language) that is not "factual" knowledge.

This means that some traditional philosophical problems regarding the foundation of empirical science (like e.g. the ground for the Law of Causality; see 5.135) are not part of natural science.

Compare with Rudolf Carnap's Scheinprobleme in der Philosophie (1928 – translated as “Pseudoproblems in Philosophy”), §7. Factual Content as a Criterion for the Meaningfulness of Statements :

The meaning of a statement lies in the fact that it expresses a (conceivable, not necessarily existing) state of affairs. If the statement expresses a state of affairs then it is in any event meaningful; it is true if this state of affairs exists, false if it does not exist.

Regarding Occam's maxim (more a catchword than a philosophical idea) see 3.328 and 5.47321.

  • i get it, yeah. he demarcates philosophy almost?
    – user38026
    Commented Apr 19, 2019 at 7:49
  • do you mean 'compare' or 'contrast'?
    – user38026
    Commented Apr 19, 2019 at 10:23

You must log in to answer this question.