 A more common view is that the lesson of Bell’s theorem is that there may be correlations that are not explicable in terms of cause-effect relations. This involves rejection of the Common Cause Principle (see, e.g., van Fraassen 1982, Fine 1989, Butterfield 1992, Elby 1992). Others have maintained that, though the Common Cause Principle as formulated by Reichenbach is to be rejected, the principle has been formulated too narrowly, and  needs to be reformulated in light of quantum phenomena. Some have suggested that despite not satisfying Reichenbach’s principle, correlations violating Bell inequalities are due to a common cause in their past, namely, the process that created entanglement (Unruh 2002, 136). Hofer-Szabo, Rédei, and Szabo (1999, 2002) have suggested a modification of the common cause principle, as have Leifer and Spekkens (Leifer 2006, Leifer and Spekkens 2011). See Cavalcanti and Lal (2014) for discussion and a critique of these proposals.