Abstracts

Can Imagination Provide Evidence for Possibility?

Daniel Dohrn Humboldt University of Berlin

Hume puts the classical conceivability-possibility link in terms of imagination. Contemporary philosophers like Yablo and Williamson agree. Others disagree. I defend the use of imagination for justifying modal claims against relevant alternatives and scepticism.

What concerns alternatives, I discuss a rationalist and a concept-based account. Against rationalism, I present intuitive examples of modal judgement where imagination plays a role. Against concept-based views of conceivability, I argue that such views need a smooth factorisation of a conceptual and a factual component of modal knowledge. I provide a counterexample to such a factorisation.

What concerns alternatives, I discuss a rationalist and a concept-based account. Against rationalism, I present intuitive examples of modal judgement where imagination plays a role. Against concept-based views of conceivability, I argue that such views need a smooth factorisation of a conceptual and a factual component of modal knowledge. I provide a counterexample to such a factorisation.

Coming to scepticism about imagination, I outline three conflicting tendencies in philosophers’ talk of ‘imagination’:

(i) A quick argument shows that imagination precisely tracks metaphysical possibility: ‘imagine’ can be used to express subjunctive suppositions (counterfactuals) which are logically equivalent to modal claims.

(ii) Many philosophers insist that imagination is more limited than supposition. It is difficult to imagine a chiliagon, but we may easily suppose one to exist. The difference is explained by imagination being restricted to mental imagery.

(iii) Some philosophers argue that imagination is too unregimented to provide modal knowledge. Anything can be imagined. For instance, one can write a story where someone has refuted Gödel’s Theorem.

To rebut scepticism arising from (ii), I start from a core use of imagination. Most philosophers agree that mental imagery can be used to settle everyday modal questions, for instance whether the piano in my apartment could be hauled upstairs. I observe that even such everyday modal tasks require imagery to be constrained by folk physics. Since folk physics may be replaced by increasingly complex theoretical input, I argue that imagery does not constitute a natural boundary of cognitive tasks involving imagination. However, the more tenuous the connection to imagery, the more pressing the question becomes what precisely the contribution of imagination is. I propose that use of imagination is not confined to imagery but involves a flexible cluster of different aspects: imagery, emotion, narrative structure, caserelatedness, and so on. It can be compared to fiction, which according to Stacey Friend cannot be neatly delimited either but permeates everyday reasoning.

To rebut doubts arising from (iii), I outline a unified account of imagination which integrates more and less constrained uses, for instance use for subjunctive suppositions in contrast to the Gödel story. I adopt a framework developed by Peter Langland-Hassan. He distinguishes an attitudinal and a content component, the latter differentiated into an imagery and a propositional part. Variations in the attitudinal component ensure that different constraints are in place when using imagination for different tasks, e.g. processing a subjunctive supposition as contrasted to writing a fictional story.

What remains to be explained is the intuition that imagination is more restricted than supposition. My proposal: we naturally understand the request to imagine things like a chiliagon as a request to provide imagery. So we do not have a boundary of imagination as such but of a certain natural way of using imagination.