Abstract

In an influential series of papers, Cleland (2001, 2002, 2011) argued that historical natural scientists employ a distinctive methodology—which exploits Lewis (1979)s asymmetry of over determination—that is capable of putting knowledge of the deep past on an epistemic par with experimental knowledge. Currie (2018) clarified the nature of the asymmetry claim and used it to argue for a more restricted form of optimism toward the historical sciences. This optimism is licensed by the evidential redundancy that the asymmetry of over determination guarantees.In this chapter I show that the argument for the asymmetry of over determination is circular and the thesis is false. Over determination toward the past is smuggled in from the start by ruling out of consideration so-called backtracking counterfactuals. By banning backtracking counterfactuals, consideration is restricted to possible worlds in which the over determination thesis holds. But in the actual world, the present is compatible with many different histories.