Abstract
The stated aim of this investigation is to clarify and critically examine the philosophical concepts inherent in the cosmological argument: he aspires to investigate the argument rather than to either refute critics or support defenders. He treats both the thirteenth century versions of Aquinas and Duns Scotus and the eighteenth century versions developed by Samuel Clarke and Leibniz, but attaches greater importance and spends more time with the latter, finding them both more sophisticated and more fruitful for investigation. The eighteenth century forms make no use of "what many philosophers would regard as a strange and perhaps nonexistent kind of causal series" and, according to the author, are more relevant because modern objections, e.g. those of Hume and Russell, aim at the eighteenth century forms.