Moses Lowman's 'Argument to prove the Unity and Perfection of God _a priori_' was published in 1735, and reprinted, with a preface by Dr Pye Smith, containing an account of the author and his works, in the Cabinet Library of Scarce and Celebrated Tracts (1836). I reproduce the abstract which Dr Smith gave of this ingenious argument in his 'First Lines of Christian Theology:' "1. Positive existence is possible, for it involves no contradiction. 2. All possible existence is either _necessary_, which must be, and in its own nature cannot but be; or _contingent_, which may be or not be, for in neither case is a contradiction involved. 3. _Some_ existence is _necessary_: for, if all existence were contingent, all existence might not be as well as might be; and that thing which might not be never could be without some other thing as the prior cause of its existence, since every effect must have a cause. If, therefore, all possible existence were contingent, all existence would be impossible; because the idea or conception of it would be that of an effect without a cause, which involves a contradiction. 4. Necessary existence must be _actual_ existence: for necessary existence is that which must be and cannot but be--that is, it is such existence as arises from the nature of the thing in itself; and it is an evident contradiction to affirm that necessary existence might not be. 5. Necessary existence being such as must be and cannot but be, it must be _always_ and cannot but be always; for to suppose that necessary existence could begin to be, or could cease to be--that is, that a time might be in which necessary existence would not be--involves a contradiction. Therefore, necessary existence is without beginning and without end--that is, it is eternal. 6. Necessary existence must be _wherever_ any existence is possible: for all existence is either contingent or necessary; all contingent existence is impossible without necessary existence being previously as its cause, and wherever existence is possible it must be either of a necessary or a contingent being. Therefore, necessary existence must be wherever existence is possible--that is, it must be _infinite_. 7. There can be but _one_ necessarily existent being; for two necessarily existent beings could in no respect whatever differ from each other--that is, they would be one and the same being. 8. The one necessarily existent being must have _all possible perfections_: for all possible perfections must be the perfections of some existence; all existence is either necessary or contingent; all contingent existence is dependent upon necessary existence; consequently, all possible perfections must belong either to necessary existence or to contingent existence--that is, to contingent beings, which are caused by and are dependent upon necessary being. Therefore, since there can be but one necessarily existent being, that being must have all possible perfections. 9.