Jump to content
Objectivism Online Forum
Sign in to follow this  
Boydstun

Peikoff's Dissertation

Recommended Posts

5 hours ago, merjet said:

Thank you for that, Stephen, especially for the distinction between logical necessity and physical necessity. Also, I liked your comments about John Locke. I have began a series on my blog about inference and necessity. Here is the first: Blanshard on Implication and Necessity #1. More to come. 

My integrative and conceptual powers applied to a lifetime of experience still leave me scratching my head.  Is this distinction an academic and historical characterization of what philosophers thought or think or is a first hand distinction of a proper philosophy?

Is the distinction as follows: physical necessity IS metaphysical i.e. identity, and logical necessity IS epistemological i.e. non-contradiction?

Share this post


Link to post
Share on other sites

The weed-vine example strikes home to anyone who has tried it. In the example, a flowering vine, in the garden, pole beans, cucumber, to a lesser extent squash and pumpkin. Pulling the weed-vine meant being able to distinguish without being able to see, or where finding a viewing angle was just downright awkward.

I took the physical-logical necessity as a neat example of ontologically based logic.

Share this post


Link to post
Share on other sites
50 minutes ago, StrictlyLogical said:

Is the distinction as follows: physical necessity IS metaphysical i.e. identity, and logical necessity IS epistemological i.e. non-contradiction?

The distinction I have in mind is different, but not incompatible with that. Physical necessity is about physical things. Logical necessity is broader, and includes the sort of necessity one can grasp in, say, higher mathematics. For example, this consequence is logically implied by this theorem. For example, this function is differentiable, therefore continuous. The reverse may be true, too, but not always.

Edited by merjet

Share this post


Link to post
Share on other sites

I concur with the distinction Merlin draws between physical and formal necessity in the preceding post. That’s a good example from mathematics, and I should note additionally that (i) it is a fact—ascertained in the way one does for mathematics—that there are some continuous functions that are nowhere differentiable, and it remains a fact even if it is the case that there simply is nothing physical to which some such function applies and that (ii) we find great success in technology and in extending comprehension of the physical by applying many functions, each one both continuous and differentiable, to electricity, to fluids, and to solids, yet understanding perfectly well that such things are discontinuous at small enough scales. 

SL, I should not want to equate the physical with the metaphysical. When Rand claims that only living things can have values or when philosophers from time immemorial say nothing comes from nothing, those claims are consonant with modern physical science, but the claims are made in what I’d call a metaphysical perspective, not a scientific one.

In his 1967 essay “The Analytic-Synthetic Dichotomy” Peikoff has a section on the traditional distinction within metaphysics between necessary and contingent facts (and how this feeds into the A-S distinction). The meaning of metaphysical necessary/contingent has changed over the centuries, but there is family-descendant resemblance under the continuing distinction. Peikoff did not think such a distinction is correct to make within metaphysics. However, he there drew a distinction between the metaphysical and the manmade (in tune with Rand’s later elaboration). Human free will is the root fact for this distinction. Unfortunately, Peikoff and Rand thought that the rule of Identity in metaphysics entailed complete determinism throughout metaphysics as contrasted with the realm of free will. Furthermore, Rand thought that such metaphysics rightly constrains (a bit) what physical science might find, but that the reverse flow does not soundly occur. That is, she thought metaphysical fundamentals could not be changed in light of advances in science. So for example, the development of chaos theory in the classical regime of physics (starting in the 1970’s as I recall) and the distinction within physics between a classical system in its regular regime as opposed to being in its chaotic regime could not suggest any reformation of general metaphysics. Really, the total determinism that Rand-Peikoff attached to metaphysics under identity was an inheritance from modern physics (Laplace et al.) and is not properly part of right metaphysics, rather should be left open for physics to settle. In his book OPAR, Peikoff does acknowledge that when it comes to value theory, biology supplies the characterized phenomena, pertinent for philosophical fundamentals concerning value.

In his dissertation, Merlin, Peikoff included Blanshard’s books The Nature of Thoughtand Reason and Analysis. He does not cite the former in his text or notes. He cites and makes specific explicit use of the latter from its pages 252–54 and 271–75. The former stretch lays out the traditional view that necessity (the one, as it happens, to be most often sainted by philosophers traditionally) arises only at the level of universals and essences; discerned at the level of conception, not perception. The latter stretch concerns conventionalist theories of logic.

Merlin, I’ve inclined to the view of logic put forth by Rand (1957) and Branden (c. 1968) and Peikoff (1967, 1991) in their orientation towards logic as tool for successful thinking. (I reject Rand’s definition of logic in its differentia. I expect she was misled by a remark in Aristotle’s Metaphysics, which seems oblivious to his great achievement, theory of the syllogism, in Prior Analytics.) It has seemed plain that on the Objectivist orientation towards logic, material implication should not be incorporated. A lot of other thinkers have thought material implication off the mark for deficiency in the relevance factor, as had Blanshard. They developed Relevance Logic (also called Relevant Logic) as replacement for classical modern logic, and I think that the way to go and a way consonant with Objectivism also. I have books telling the history, concerns, and purposes that brought on material implication, but I’ll have to open them. I’ll let you know on your blog what I find.

Share this post


Link to post
Share on other sites
4 minutes ago, Boydstun said:

SL, I should not want to equate the physical with the metaphysical. 

Just to clarify, when I say physical x is metaphysical, I mean it in the sense I would say a crow is an animal.

Share this post


Link to post
Share on other sites

I had meant to mention in the preceding post that Peikoff 1964 notes that not all classical philosophers subscribed to a metaphysical distinction between the necessary and the contingent. He helpfully mentions John Scotus Erigena, Spinoza, and Hegel.

~~~~~~~~~~~~~~~~

Links to the sections of this essay so far:

Plato

Aristotle I  II   

Kant I  II  III

Conventionalism I  II  III

Edited by Boydstun

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...