(The following are the Rosenthal/Harnad exchanges excerpted from the full discussion, which also included exchanges with students.)

David Rosenthal: Does Consciousness Have any Utility?

Presented at Turing Centenary Summer Institute on the 

Evolution and Function of Consciousness

Université du Québec à Montreal

June-July 2012

David Rosenthal   


      Abstract: It is plain that an individual's being conscious and an individual's being conscious of various things are both crucial for successful functioning.  But it is far less clear how it might also be useful for a person's psychological states to occur consciously, as against those states occurring but without being conscious.  I'll restrict attention here to cognitive and desiderative states, though similar considerations apply to perceiving, sensing, and feeling; like cognition and volition, all these states are useful; the question is whether any additional utility is conferred by any of these states' occurring consciously, and I'll offer reasons to think not.  It has been held that cognitive and volitional states' being conscious enhances processes of rational thought and planning, intentional action, executive function, and the correction of complex reasoning.  I examine  these and related proposals in the light of empirical findings and theoretical considerations, and conclude that there is little reason to think that any additional utility results from these states' occurring consciously.

      If so, we cannot rely on evolutionary adaptation to explain why such states so often occur consciously in humans and likely many other animals.  Elsewhere (Consciousness and Mind, Clarendon, 2005) I have briefly sketched an alternative explanation, on which cognitive and desiderative states come to be conscious as a byproduct of other useful psychological developments, some involving language.  But there is still no significant utility that these states' being conscious adds to the utility of those other developments.


      Rosenthal, D Consciousness and Its Function Neuropsychologia 46, 3 (2008): 829-840.