I'll comment on this post:
A basic problem with Andrew's exposition of divine simplicity is that he doesn't address the most controversial refinement. Proponents of divine simplicity often deny that God has any distinct properties or contingent relations. This leads to serious theological confusion. Let's take two examples:
i) A sine qua non of Calvinism is the distinction between God's justice and God's mercy. God is never unjust, but God is sometimes unmerciful. These aren't merely distinct, but sometimes divergent. If, however, justice and mercy are identical, then that erases the distinction between salvation and judgment, election and reprobation.
ii) Calvinists typically grant the traditional distinction between God's absolute power and his ordinate power. Likewise, the Westminster Confession affirms God's counterfactual knowledge (WCF 3.2).
In modern jargon, this is cashed out in terms of possible worlds. The actual world is not the only possible world. Rather, God was at liberty to decree a different world.
If, however, there is no contingency in God's knowledge, volition, or actions, then you have a necessitarian scheme in which everything that happens is absolutely inexorable. It could not be otherwise, even for God. By contrast, Calvinism typically affirms conditional necessity rather than absolute necessity. Put another way, if God does different things in different possible worlds, then God can't be simple–in this radical sense.
Other readers might immediately wonder how this fits with the Trinity, and they are right to raise the question. However, when the Christian tradition spoke of the Trinity, it must be understood that their entire way of explaining it agreed with simplicity. They explained it in such a way that it could be consistent with this idea. If it seems hard to understand how they could do so, they would agree: They taught that the Trinity was a mystery that was beyond complete human comprehension.
I think that's an illicit appeal to paradox. I have not antecedent objections to mystery or paradox in Christian theology. However, that applies to revealed truths, viz. the Trinity. By contrast, divine simplicity is basically an artifact of philosophical theology. Insofar as philosophical theology relies on natural reason rather than divine revelation, it ought to be accessible and accountable to rational scrutiny.
They did, however, come up with a way of explaining all the scriptural data that pressed the church to formulate the doctrine of the Trinity, and it should be said, among those data was the explicit scriptural witness to monotheism. Explanations of the threeness of God that amount to teaching there are three divine beings runs up against not simply squaring themselves with simplicity, but also with monotheism. And indeed, the larger argument of the classical tradition would be that those two ideas, divine simplicity and monotheism, are not accidentally linked, but rather are two sides of the same coin.
i) That's equivocal because it confounds simplicity with singularity or unicity. To affirm that there is only one God hardly entails that God has no distinct properties or contingent relations.
ii) In addition, I'm struck by how many Christians think it's more important to protect the Trinity against the appearance of tritheism than unitarianism. Yet unitarianism is at least as heretical as tritheism.
Finally, Andrew expounds Dyotheletism, but he doesn't explain the relevance of that issue to EFS.