9:38 a.m.
*Speaker:
Franz Berto (U. St Andrews & ILLC, U. Amsterdam)
*Title:
Half Empty vs Half Full: Belief Revision and the Framing Effect
*Abstract:
The dominant logical theory of belief revision, AGM (Alchourron, Gärdenfors and Makinson),
imposes an amount of idealisation on cognitive agents revising their beliefs in the light
of new information: their belief states are perfectly consistent, closed under the full
force of classical logic, and they know all logical truths. Humans are not like that: they
can hold inconsistent beliefs; their belief states are not classically closed; and they
can be subject to framing effects, revising their beliefs in different ways when presented
with logically equivalent options (‘If you apply for the job, you have 40% chances of
making it’ vs ‘… you have 60% chances of failing’). Behavioural economics has shown the
momentous consequences of framing in social choice and decision theory, where presenting
the same situation positively (‘glass half full’) or negatively (‘glass half empty’) can
lead to dramatically different beliefs and choices. In this talk, I present a semantics
for a belief revision operator which is hyperintensional, that is, capable of modelling
distinctions more fine-grained than classical logical equivalence, and in particular,
framing effects and inconsistent beliefs. Unlike most approaches to belief revision for
non-ideal agents, my semantics does not resort to non-classical logics. The framework
combines, instead, a standard semantics for propositional modal logic with a simple
mereology of contents.
*Bio:
Franz Berto is the chair of logic and metaphysics at the university of St Andrews and a
research chair at the Institute for Logic, Language and Computation at the university of
Amsterdam. He works more or less on anything nonclassical: non-standard ontology,
non-classical modal and epistemic logic, and the philosophy of parallel computation. He
has written a number papers on these topics, and books with Oxford University Press,
Blackwell, King’s College, Synthese Library, Bloomsbury. He has held research positions at
the Institute for Advanced Study at the University of Notre Dame, at the Sorbonne and
CNRS in Paris, at the University of Aberdeen, and at the Netherlands Institute for
Advanced Study.
*When:
Thursday 7th of June 2018, 12:00-13:00
*Location:
Manno, Galleria 1, 2nd floor, room G1-204
*Registration:
Pizza (or alternative food) and drinks will be offered at the end of the talk. If you plan
to attend, please register in a timely fashion at the following link so that we will have
no shortage of food:
https://doodle.com/poll/24yvbd6rgs68zarx