Logic and Politics

Franca D'Agostini

Graduate School of Economic, Political and Social Sciences, State University of Milan, Italy

and Polytcehnical School of Turin, Italy

The tutorial includes a brief account of theories about the relations between logic and politics, then three lectures devoted to practical cases, illustrating the use of non-classical logics in political reasoning and public debate.

1. The relations between logic and politics: hypotheses and programs
2. Non-classical logics and politics:
- Disagreements, gaps and gluts
- Political pluralism and modal logics
- Ideology as coherence without truth

Between politics and logics (like between politics and truth) there is traditional foreignness  or  even  enmity.  In  ‘realistic’  perspective,  political  life  is  alleged  to  be refractory to logic and rationality, insofar as ruled by powers and interests. In normative political theory, logic is alleged to be damage more than advantage for public life, for instance  because  the  compelling  force  of  logical  proofs  may  promote  intolerant  and context-insensitive attitudes, so it is hardly adaptable to the needs of political pluralism.
And yet, one may also see that there is close connection between logic, strictly intended as formal theory of valid inference, and politics, especially democratic politics. Democracy, in John S. Mill’s famous definition, is «government by discussion», and human discussions are also if not primarily ruled, for good or ill, by the formal validity of arguments (I can hardly believe that p, if I believe that p       q, and    q). So it is reasonable to admit that common citizens’ and politicians’ logical competence is one of the basic features of healthy associated life. But which sort of logical competence? And in which sense logic (as technique of formal validity) intersects politics in a significant way?

The adversaries of logic in political philosophy (see classically H. Arendt, J. Rawls, J. Habermas) generally have a fairly restricted conception of logic: they conceive it as study of classical forms as applied to mathematically-oriented ways of thinking. But this is not all what logic is and can be (like the «universal logic» enterprise is intended to show).
The importance of a certain kind of ‘logic’ for politics is admitted by some theorists of deliberative  or  direct  democracy  (see  also  the  neo-Socratic  approach  to  democracy proposed by M. Nussbaum and A. Sen). But usually, the ‘logic’ involved in these perspectives is not the formal theory of validity, but informal logic, or theory of argumentation, or critical thinking. All these techniques and disciplines can be useful, but only for a basic education of citizens in classical logic, and they do not seem to capture the real intersection of politics and logic, in the effective practice of political reasoning and arguing.
Some neo-structuralist thinkers (such as G. Deleuze or A. Badiou) have proposed a vision of political facts also including formal considerations, and have tried to apply some logical acquisitions (especially borrowed from structuralism) to a critical analysis of political facts. But these accounts usually have poor or null relation to the contemporary acquisitions of philosophical logic in the analytical tradition.

The tutorial is based on the idea that what is needed for politics (and political theory) is philosophical logic, in the current meaning of a series of logical inquiries concerning paradoxes, non-classical conceptions of truth and validity, and the connections between natural language and formal languages. As a matter of fact, it is not so difficult to see that political reasoning, especially in democratic perspective, is most often ruled (and should be ruled) by non-classical logics, and this can be seen in various ways, for instance:

- irreducible public conflicts usually involve under-determined or over- determined cases, so paracomplete and paraconsistent conceptions of truth may help in dealing with these sorts of conflicts;

- normative disagreements are based on conceptions of how the world is and could be, so logical awareness concerning modality – e. g. possible-worlds semantics – is highly helpful in understanding rival normative pictures of facts, saving pluralism while allowing truth-oriented confrontations;

- ‘ideology’ – in classical Marxian account – is a false system of beliefs that blocks any attempt at modifying reality to meet justice, hence logical pluralism, to say a ductile conception of validity (including classically deductive as well as Bayesian and relevant validity), provides a good antidote to ideological blindness.

The three lectures of the tutorial will deal with these three topics. Moving from the illustration of some particular cases, they will give attending people the preliminary elements for reflecting on how new acquisitions of philosophical logic may reverse the traditional judgement about the incompatibility, or enmity, or extraneousness, of logic and politics. Last but not least, they are also intended to suggest that the consideration of the real needs and occurrences of associated life can be heuristically useful for logical researches.







References (preliminary suggestions)

Arendt, H., 1999, The Human Condition. University of Chicago (1st ed. 1958)

Beall, J.C. and B. van Fraassen, 2003, Possibilities and Paradoxes. Oxford University Press

Beall, J. C. and G. Restall, 2006, Logical Pluralism. Oxford University Press

Berto,  F.,  2007,  How  to  Sell  a  Contradiction.  The  Logic  and  Metaphysics  of Inconsistency. King’s College

Burgess, J., 2009, Philosophical Logic. Princeton University Press

Cellucci, C., 2013, Rethinking Logic. Springer

Christensen, D. and J. Lackey, The Epistemology of Disagreement. New Essays. D’Agostini, F., forthcoming, Logic & Politics. A New Alliance.

Dahl, R. A., 1998, On Democracy. Yale (2000)

Garson, J. W., 2006, Modal Logic for Philosophers. Cambridge University Press

Huckfeldt, R., P. E. Johnson, J. Sprague, 2004, Political Disagreement. Cambridge
University Press

Jacquette, D., 2010, Logic and How It Gets that Way. Acumen

Petrucciani, S., 2014, Democrazia. Einaudi

Priest, G., 2010, An Introduction to Non-Classical Logics: From If to Is. Cambridge University Press (1st ed. 2001)

Read, S., 2010, Thinking About Logic. Oxford University Press (1st ed. 1994)

Williamson, T., 2013, Modal Logic as Metaphysics. Oxford University Press