  Construed as an argument against hidden variable theories, Bell's Theorem
assumes that hidden variables would be independent of future measurement
settings. This Independence Assumption (IA) is rarely questioned. Bell
considered relaxing it to avoid non-locality, but thought that the resulting
view left no room for free will. However, Bell seems to have failed to
distinguish two different strategies for giving up IA. One strategy takes for
granted the Principle of the Common Cause, which requires that a correlation
between hidden variables and measurement settings be explained by a joint
correlation with some unknown factor in their common past. The other strategy
rejects the Principle of the Common Cause, and argues that the required
correlation might be due to the known interaction between the object system and
the measuring device in their common future. Bell and most others who have
discussed these issues have focussed on the former strategy, but because the
two approaches have not been properly distinguished, it has not been well
appreciated that there is a quite different way to relax IA. This paper
distinguishes the two strategies, and argues that the latter is considerably
more appealing than the former.
