Hallucinations have long interested philosophers of perception. They are invoked to challenge what is called “naive realism”. That what we see is not always out there, reminds us that our sense of what is out there is mediated – at the very least by our senses. This has raised questions of whether what is there exists independently of our senses. The “Argument from Illusion (or Hallucination)” leads to the view that even items we regard as the basic furniture of everyday life – material objects – are merely constructs of sense experience. These venerable views are no longer mainstream. As Gilbert Ryle said, illusions cannot undermine the truth of other experiences because “there can be false coins only where there are coins made of the proper materials by the proper authorities”. And, more recently, disjunctivist philosophers have reasserted what the rest of us suspected, that veridical perceptions and hallucinations – howsoever similar – are not the same kinds of mental entities. Even so, hallucinations are a deeply disturbing reminder of how what we take for reality is under-determined by the sense experiences on which our taking is based. And the puzzle of the relationship between our perceptions, the objects we individually perceive, and what we all agree is there, remains.
Saturday, February 16, 2013
… Oliver Sacks on drugs | TLS. (Hat tip, Dave Lull.)