Dr. Alexandre Costa-Leite (Univ. of Brasilia): Logics of Partial Justification, Quasi-truth and Suspension of Judgment

Datum / Uhrzeit:
28.01.20   /  18:30 - 20:00

Institut für Theoretische Philosophie

24.53.01 Raum 81


Let p be a proposition. Sometimes, there is a justification for p and there is a justification for the negation of p. This occurs often in many real situations in sciences, math, law and philosophy, for instance. Whenever a proposition and its negation are both justified we are at the level of a partial justification. How should we understand these justifications? Are there logics to deal with them? Examples of logics to manage partial justification are presented departing from standard justification logics (cf. [3] and [1]) and it is showed how they are connected with the concept of quasi-truth (see [2] and [4]) and with modes of suspension of judgment (see [5]).

[1] Artemov, S. (2008). The logic of justification. The Review of Symbolic Logic,  1(4), pp. 477–513;
[2] da Costa, N. (1986). Pragmatic probability. Erkenntnis, 25(2), pp. 141–62;
[3] da Costa, N. (1999). O conhecimento científico. 2a.ed. São Paulo: Discurso Editorial;
[4] Mikenberg, I; da Costa, N; Chuaqui, R. 1986. Pragmatic truth and approximation to truth.
The Journal of Symbolic Logic, 51(1), pp. 201–21;
[5] Empiricus, S. (2005). Outlines of scepticism. Edited by Julia Annas and Jonathan Barnes.
Cambridge: Cambridge University Press.

Alexandre Costa-Leite teaches Logic and Philosophy (Professor Adjunto) at the Department of Philosophy of the Universidade de Brasília (BR, since 2009). PhD in Logic from the Université de Neuchâtel (CH, 2007), visiting scholar at The City University of New York (USA, 2007-2008) and associate researcher of the Centre for Logic, Epistemology and History of Science at the Universidade Estadual de Campinas (BR, 2008-2012). His research interests are in the domains of Non-Classical Logics and Metaphysics.

Selected recent publications

de Souza, E; Costa-Leite, A; Dias, D.H.B. (2019).  Paradeduction in Axiomatic Formal Systems. Logique et Analyse, 62(6), pp. 161-176; 
Costa-Leite, A. (2018). Oppositions in a line segment.  South American Journal of Logic, 4(1), pp.185-193;
Costa-Leite, A. (2016). Interplays of knowledge and non-contingency. Logic and Logical Philosophy, 25(4), pp.521-534;


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