Things could not have been produced otherwise
Formal Statement
Things could not have been brought into being by God in any manner or in any order different from that which has in fact obtained.
In Plain Language
This is the full-strength version of determinism. It is not just that things happen to be caused — they could not have been otherwise. There are no unchosen possibilities sitting in a divine mind. The actual order of nature is the only possible order, because it follows from God's nature, and God's nature is necessary. This seals the exit doors: no Plan B, no alternative history, no divine whim.
Why This Follows
Steps 1 and 2 (df-01, df-02) gave us universal necessity and the denial of free will even in God. This step draws the explicit consequence: if God's nature necessitates everything, and God's nature could not have been otherwise (being self-caused), then the order of things could not have been otherwise either.
Anti-contingency is not a side-effect of the system — it is an explicit theorem.
Connected Concepts
Does the claim that "things could not have been otherwise" feel oppressive to you? Hold that reaction — we will return to it.