The non-Christian worldview does not share a metaphysic or epistemology with Christianity with respect to unity and plurality. Some non-Christians are emphatic about the ontological one-ness or unity of everything to the exclusion of any plurality. If it is the case that ultimately everything is ontologically unity then the plurality (e.g. two, many, distinctions, otherness, etc.) that might be assumed with respect to things is principally unintelligible. The reason for this is that if reality is ultimately “one” then distinctions of any sort are impossible – which is absurd. Alternatively, if plurality is ontologically ultimate then there can be no relations between anything. Epistemology is rendered impossible again. The non-Christian who wants to affirm anything is stuck on the philosophical problem of the “one and many.” In order to be consistent with the non-Christian worldview, the non-Christian must deny the Christian’s epistemological answer to the “problem,” leaving no solution from within the non-Christian worldview. Yet this denial of ontologically co-ultimate unity and plurality is not consistent with the implicit acceptance of the same throughout the non-Christian’s epistemology and so a contradiction results.
The problem of unity and plurality, or the “one-and-many,” is another problem of connection. The Christian apologist can exploit this problem to its fullest as the truest expression of the problem of connection for the non-Christian worldview and the coherence of the Christian worldview found in the unique doctrine of the Trinity. Not only does the problem of unity and plurality come up with respect to most anything that assumes some sort of relationship, but it is an alternative way to understand more complex philosophical problems of skepticism. For example, in the previous part of this introduction, we discussed logic. Logic can be thought of as consisting of unifying principles, and the contingent realm or external world that we use logic to describe and otherwise think about as plurality exhibited through particularity and change. Or, we might think of the so-called “problem of induction” as requiring some type of regularity, connection, or unity between the plurality of events or entities. We will discuss this problem in more detail in the next part of this introduction.
The common idea in presuppositionalists circles is that this solves the problem of the one and the many. That the diversity and unity in the Godhead are co-ultimate. The problem is when Eternal Generation is presented into the discussion. This ultimately leaves the Father’s unity as supreme in the Godhead. This leaves only the monarchy of the Father with no exceptions. If we maintain that the person of the Son is caused to be by the Father’s act of generation, then it seems to be that they aren’t co-ultimate.