Godfrey-Smith (1993) argues that systemic concepts of function do permit attributions of malfunction. He argues that a token component in a system is malfunctioning when it cannot play the role that lets other tokens of the same type feature in the explanation of the larger system. Davies (2003, 212) denies this. He says that functional types are defined in terms of what they can do and that if a component cannot carry out its normal contribution to the overall system then it ceases to be a memb