 Scholars are still debating the influence of Collins on David Hume (1711–1776). How much influence is attributed to Collins depends largely on the interpretation given to Hume’s philosophy (see McIntyre 1994, Russell 1995, and Harris 2005). McIntyre and Russell despite their differences agree that in A Treatise Of Human Nature Hume was systematically attacking Clarke’s position on the mind/body relation as articulated both in Clarke’s Boyle lectures and the Clarke Collins correspondence of 1707–08 and that many of Hume’s arguments resemble those of Collins. Harris, focusing on the issue of free will and determinism and using the Enquiries to interpret the Treatise, has a contrasting view. He argues that Hume’s account of necessity is weaker than “that defended by Collins and before him by Hobbes”, and he goes on to claim that in giving this weaker account Hume is giving the same kind of account that Bramhall and Clarke gave in trying to find a middle way between necessitarianism and the liberty of indifference (Harris 2005: 73). Harris may be correct in noting a variety of ways in which Hume’s account of causality and necessity differs from that of Hobbes, Locke and Collins. On the other hand, central to Hume’s analysis of causality is the total rejection of the a priori Homogeneity Principle and the necessary connection implicit in heirloom theories of causality. Collins also rejects the Homogeneity Principle, and heirloom theories of causality that underlie it. He strenuously denies that any of the contradictions that are supposed to follow from violating the Principle actually occur. These are clear similarities between Collins’ account of causality and Hume’s that Harris fails to note. I think these considerations tend to weaken Harris’ judgement that while Collins is a dogmatist on these issues, Hume is a skeptic (see Harris 2005: note 22 p. 79). 