Om mig
Born in 1982 in Växjö, Sweden. Philosophical interests include
philosophy of language, logic, mathematics, modality, rationality, probability and science.
Publikationer
I urval från Stockholms universitets publikationsdatabas
Avhandling (Dok) Analyticity, Necessity and Belief2017. Eric Johannesson (et al.).
A glass couldn't contain water unless it contained H2Omolecules. Likewise, a man couldn't be a bachelor unless he was unmarried. Now, the latter is what we would call a conceptual or analytical truth. It's also what we would call a priori. But it's hardly a conceptual or analytical truth that if a glass contains water, then it contains H2Omolecules. Neither is it a priori. The fact that water is composed of H2Omolecules was an empirical discovery made in the eighteenth century. The fact that all bachelors are unmarried was not. But neither is a logical truth, so how do we explain the difference? Twodimensional semantics is a framework that promises to shed light on these issues. The main purpose of this thesis is to understand and evaluate this framework in relation to various alternatives, to see whether some version of it can be defended. I argue that it fares better than the alternatives. However, much criticism of twodimensionalism has focused on its alleged inability to provide a proper semantics for certain epistemic operators, in particular the belief operator and the a priori operator. In response to this criticism, a twodimensional semantics for belief ascriptions is developed using structured propositions. In connection with this, a number of other issues in the semantics of belief ascriptions are addressed, concerning indexicals, beliefs de se, beliefs de re, and the problem of logical omniscience.

2016. Eric Johannesson, Sara Packalén. Thought 5 (3), 169176
Many expressions intuitively have different epistemic and modal profiles. For example, coreferring proper names are substitutable salva veritate in modal contexts but not in beliefcontexts. Twodimensional semantics, according to which terms have both a socalled primary and a secondary intension, is a framework that promises to accommodate and explain these diverging intuitions. The framework can be applied to indexicals, proper names or predicates. Graeme Forbes (2011) argues that the twodimensional semantics of David Chalmers (2011) fails to account for socalled nested contexts. These are linguistic contexts where a sentence is embedded under both epistemic and modal operators. Chalmers and Rabern (2014) suggest a twodimensional solution to the problem. Their semantics solves the nestingproblem, but at the cost of invalidating certain plausible principles. We suggest a solution that is both simpler and avoids this cost.

2015. Eric Johannesson. Filosofisk Tidskrift (2)

Artikel MontyHall problemet2017. Eric Johannesson. Filosofisk Tidskrift

Artikel Goodmans induktionsproblem2014. Eric Johannesson. Filosofisk Tidskrift (4)

2018. Eric Johannesson. Journal of Philosophical Logic
When it comes to Kripkestyle semantics for quantified modal logic, there’s a choice to be made concerning the interpretation of the quantifiers. The simple approach is to let quantifiers range over all possible objects, not just objects existing in the world of evaluation, and use a special predicate to make claims about existence (an existence predicate). This is the constant domain approach. The more complicated approach is to assign a domain of objects to each world. This is the varying domain approach. Assuming that all terms denote, the semantics of predication on the constant domain approach is obvious: either the denoted object has the denoted property in the world of evaluation, or it hasn’t. On the varying domain approach, there’s a third possibility: the object in question doesn’t exist. Terms may denote objects not included in the domain of the world of evaluation. The question is whether an atomic formula then should be evaluated as true or false, or if its truth value should be undefined. This question, however, cannot be answered in isolation. The consequences of one’s choice depends on the interpretation of molecular formulas. Should the negation of a formula whose truth value is undefined also be undefined? What about conjunction, universal quantification and necessitation? The main contribution of this paper is to identify two partial semantics for logical operators, a weak and a strong one, which uniquely satisfy a list of reasonable constraints (Theorem 2.1). I also show that, provided that the point of using varying domains is to be able to make certain true claims about existence without using any existence predicate, this result yields two possible partial semantics for quantified modal logic with varying domains.