 On Wierenga's second move, there is no such thing as truth simpliciter. Rather, all truth is truth at a perspective (a pair &lt;S, t&gt; of a person and a time).  If I am sitting now but was not sitting at midnight, the second move does not say that the proposition &lt;I am sitting&gt; first was not true and then was. Rather, it says that &lt;I am sitting&gt; is true at &lt;me, now&gt; but was false at &lt;me, midnight&gt;. Given this machinery, Wierenga defines omniscience this way: x is omniscient just if for all propositions p and perspectives &lt;S, t&gt;, if p is true at &lt;S, t&gt;, x knows this, and if x is at &lt;S, t&gt; and p is true at &lt;S, t&gt;, x knows that p. With these moves, it's easy to show that atemporal (and so immutable) omniscience is possible if there can be such a thing as an atemporal perspective. If so, those pushing (1)–(4) can rule out immutable omniscience only if they can provide independent reason to think that necessarily, all perspectives are temporal.  If they have that, of course, they do not need (1)–(4), because if God is temporal and persists, His perspective changes and so what He must know to be omniscient changes. Thus (1)–(4) turns out dialectically impotent and otiose.