Fundamento ontológico del "Modus ponens " .... Estoy perplejo...

El año pasado, en el XV EIDL o el anterior, no recuerdo, estando en México discutí con un eximio Doctor acerca de las posturas realistas en Lógica , que tanto me intrigan y no dejan de sorprenderme.
Resulta que la conversación llegó a su cumbre cuando el Colega me dijo : "Yo no dudo que haya un fundamento ontológico del Modus ponens"...(y no supo más qué decir).
Me pareció de buen gusto finalizar ahí esa discusión inútil  y pensé que encontrar el fundamento ontológico del modus ponens era una tarea tan fantasiosa como completar el Árbol de Porfirio por el lado derecho.

Sin embargo, en un artículo que aparecerá en el 2014 (The Metaphysical Interpretation of Logical Truth
TUOMAS E. TAHKO) aparece el fundamento metafísico realista del Modus Ponens. Se los comparto.

"Very briefly, we might consider the case of modus ponens (A∧(A→B))→B). If

thought of as a rule, it may seem difficult to apply it to the world in the sense that I have suggested with regard to LNC. (1) Yet, there do appear to be clear cases of physical phenomena that feature a modus ponens type structure. As a first pass, causation might be offered as a candidate of ‘real world modus ponens’, but there are obvious complications with this suggestion, as it depends on one’s theory of causation. However, there are, perhaps, better candidates. Take the simple case of an electron pair in a closed system, where two electrons occupy the same orbital. As we’ve already observed, two electrons in a closed system are governed by the Pauli Exclusion Principle. In particular, since the electrons cannot be in the same quantum state at the same time, we know that the only way for them to occupy the same orbital (i.e., having the same orbital quantum numbers) is for them to differ in spin (i.e., to have different spin quantum numbers). Accordingly, when we observe electron A having spin-up, we immediately know that any electron, B, on the same orbital as A must have spin-down. Moreover, there can be only two electrons on the same orbital and they must always have opposite spin.

It is easy to see how this situation could be interpreted as a real world modus ponens type case. Even better, we only needed to refer to one fundamental physical principle to make this case."

(1) (LNC) The same attribute cannot at the same time belong and not belong to the same
subject in the same respect and in the same domain.

La verdad es que no me convence....

The Metaphysical Interpretation of Logical Truth TUOMAS E. TAHKO

Final version to appear in Penelope Rush (ed.), The Metaphysics of Logic: Logical Realism, Logical Anti-Realism and All Things In Between (CUP, 2014).


ABSTRACT
The starting point of this paper concerns the apparent difference between what we might call absolute truth and truth in a model, following Donald Davidson. The notion of absolute truth is the one familiar from Tarski’s T-schema: ‘Snow is white’ is true if and only if snow is white. Truth in a model, or relative truth, instead of being a property of sentences as absolute truth would appear to be, is evaluated in terms of the relation between sentences and models.
I wish to examine the apparent dual nature of logical truth (without dwelling on Davidson), and suggest that we are dealing with a distinction between a metaphysical and a linguistic interpretation of truth. I take my cue from John Etchemendy’s work, who suggests that absolute truth could be considered as being equivalent to truth in the ‘right model’, i.e., the model that corresponds with the world. However, the notion of ‘model’ is not entirely appropriate here, as it is closely associated with relative truth. Instead, I propose that the metaphysical interpretation of truth may be illustrated in modal terms, metaphysical modality in particular. One of the tasks that I will undertake in this paper is to develop this modal interpretation, partly building on my previous work on the metaphysical interpretation of the law of non-contradiction (Tahko 2009).
After an explication of the metaphysical interpretation of logical truth, a brief study of how this interpretation connects with some recent important themes in philosophical logic follows. In particular, I discuss logical pluralism and propose an understanding of pluralism from the point of view of the metaphysical interpretation.

The Metaphysics of Logic: Logical Realism, Logical Anti-Realism and All Things In Between

I’m excited to advertise a forthcoming anthology, with Cambridge University Press, entitled The Metaphysics of Logic: Logical Realism, Logical Anti-Realism and All Things In Between. The anthology is the brainchild of Penelope Rush (Tasmania), who is editing the book. It was recently accepted for publication by Cambridge, and if everything goes smoothly I expect that you can buy it in early 2014. The proposal, which I’ve seen, looks great, and I really look forward to reading the papers. Topics include general approaches to the metaphysics of logic, such as logical realism, anti-realism, and naturalism; historical pieces on Aristotle, Bolzano, and Kant, and specific issues such as the revisability of logic and logical truth.

The metaphysics of logic is a topic which I’ve thought about before and I’m quite pleased to finally see a book length study on it. My previous related work include my 2009 paper in theAustralasian Journal of Logic, ‘The Law of Non-Contradiction as a Metaphysical Principle‘, and the older ‘The Metaphysical Status of Logic‘, based on my presentation at LOGICA 2007. In fact, The AJL paper appears to be my most read paper (based on downloads from various sources), which goes to show that the issues are topical. I’ve been meaning to return to this theme, so I’m happy to be contributing to the volume. My piece is provisionally titled ‘The Metaphysical Interpretation of Logical Truth’.

I had a great experience with CUP when I was editing my own volume, and I’ve no doubt that this volume will have the same treatment. More updates in due course!

The list of contributors is very impressive:

• Jody Azzouni, Department of Philosophy, Tufts University.
• J. C. Beall, Department of Philosophy and the Philosophy and Logic Group, University of Connecticut and University of Otago.
• Ermanno Bencivenga, Philosophy in the School of Humanities, University of California, Irvine.
• Solomon Feferman, Depts. of Mathematics and Philosophy, Stanford University.
• Curtis Franks, Department of Philosophy, University of Notre Dame.
• Gyula Klima, Professor, Department of Philosophy, Fordham University, New York.
• Sandra Lapointe, Department of Philosophy at McMaster University.
• Penelope Maddy, Department of Logic and Philosophy of Science, University of California, Irvine.
• Graham Priest, The University of Melbourne, Boyce Gibson Professor of Philosophy, and CUNY Graduate Centre Distinguished Professor of Philosophy.
• Penelope Rush, Philosophy Department, University of Tasmania.
• Stewart Shapiro, Professor, Department of Philosophy, The Ohio State University.
• Mark Steiner, Professor Emeritus of Philosophy, The Hebrew University of Jerusalem.
• Tuomas E. Tahko, Department of Philosophy, History, Culture and Art Studies, University of Helsinki.
• Paul Thom, Honorary Visiting Professor, Department of Philosophy, The University of Sydney, New South Wales.

Tags: CUP, Graham Priest, Gyula Klima, J. C. Beall, Jody Azzouni, logic, logical consequence, logical pluralism, logical truth, Penelope Maddy, Penelope Rush, philosophical logic, Stewart Shapiro