The Problem of Rational Knowledge

Erkenntnis (S6):1-18 (2013)
Mark Jago
Nottingham University
Real-world agents do not know all consequences of what they know. But we are reluctant to say that a rational agent can fail to know some trivial consequence of what she knows. Since every consequence of what she knows can be reached via chains of trivial cot be dismissed easily, as some have attempted to do. Rather, a solution must give adequate weight to the normative requirements on rational agents’ epistemic states, without treating those agents as mathematically ideal reasoners. I’ll argue that agents can fail to know trivial consequences of what they know, but never determinately. Such cases are epistemic oversights on behalf of the agent in question, and the facts about epistemic oversights are always indeterminate facts. As a result, we are never in a position to assert that such-and-such constitutes an epistemic oversight for agent i (for we may rationally assert only determinate truths). I then develop formal epistemic models according to which epistemic accessibility relations are vague. Given these models, we can show that epistemic oversights always concern indeterminate cases of knowledge
Keywords Bounded rationality  Logical omniscience  Epistemic possibility  Knowledge  Rationality
Categories (categorize this paper)
DOI 10.1007/s10670-013-9545-1
Edit this record
Mark as duplicate
Export citation
Find it on Scholar
Request removal from index
Revision history

Download options

Our Archive
External links

Setup an account with your affiliations in order to access resources via your University's proxy server
Configure custom proxy (use this if your affiliation does not provide a proxy)
Through your library

References found in this work BETA

Reasoning About Knowledge.Ronald Fagin (ed.) - 1995 - MIT Press.
Knowledge and Belief.Jaakko Hintikka - 1962 - Ithaca: Cornell University Press.
Logic for Equivocators.David Lewis - 1982 - Noûs 16 (3):431-441.
Assertion, Denial and Non-Classical Theories.Greg Restall - 2013 - In Francesco Berto, Edwin Mares, Koji Tanaka & Francesco Paoli (eds.), Paraconsistency: Logic and Applications. Springer. pp. 81--99.
The Content of Deduction.Mark Jago - 2013 - Journal of Philosophical Logic 42 (2):317-334.

View all 16 references / Add more references

Citations of this work BETA

Substructural Epistemic Logics.Igor Sedlár - 2015 - Journal of Applied Non-Classical Logics 25 (3):256-285.

Add more citations

Similar books and articles


Added to PP index

Total downloads
491 ( #6,107 of 2,293,671 )

Recent downloads (6 months)
20 ( #22,273 of 2,293,671 )

How can I increase my downloads?

Monthly downloads

My notes

Sign in to use this feature