00311pab a2200121 454500008004000000100001800040245004300058260000900101300001300110362000800123650002000131773003800151180718b2003   xxu||||| |||| 00| 0 eng d  aSteel, Daniel  aSocial mechanisms and causal inference  c2003  ap.55-78.  aMar  aSocial sciences  aPhilosophy of the Social Sciences