 Suppose that there is an \(X\) that is \(F\), and that to account for why \(X\) is \(F\) we need to appeal to another \(X\) that is also \(F\). Now there is the question as to why this \(X\) is \(F\), and so we need to appeal to another \(X\) which is also \(F\) …. If this proceeds ad infinitum, with a new \(X\) invoked at each new stage in the process, there is a concern that we end up without having accounted for the \(F\)-ness of any of the \(X\)s. If this infinite regress argument is successful then our choices are either: