 In 1729 a short book, A Dissertation of Liberty and Necessity, with the initials A.C. on the title page, was published. For a number of reasons O’Higgins holds that Collins is not the author of this work. O’Higgins first reason for rejecting Collins’ authorship is that the book treats the substance of the soul as unknown—a Lockean doctrine that Collins had rejected. O’Higgins also cites contemporary reviews that claim the arguments of the book are weak compared to the Inquiry. Jacopo Agnesina agrees with O’Higgins that the work is not by Collins and gives a full discussion of the argument over attribution (Agnesina 2018: 125–132, see also Harris 2005: 60). Still while making claims that Collins would not make about the soul and substance, the arguments are certainly consistent with the determinist position that Collins was holding in the earlier work. The author also takes into account at least one of Clarke’s criticisms of the Inquiry.