One often repeated argument against atemporalism is the argument from simultaneity (hereafter “AS”). For the life of me, I cannot figure why this argument persists even though there are much better arguments against atemporalism available (e.g. the argument from God’s knowledge of tensed propositions, or the argument from temporal becoming). Swinburne and Kenny’s formulations of the argument are usually taken as standard. According to Anthony Kenny (“Aquinas on Divine Foreknowledge & Human Freedom” in Reason and Religion, 1987):
Indeed, the whole concept of a timeless eternity, the whole of which is simultaneous with every part of time, seems to be radically incoherent. For simultaneity as ordinarily understood is a transitive relation. If A happens at the same time as B and B happens at the same time as C, then A happens at the same time as C. If the BBC programme and the ITV programme both start when Big Ben strikes ten, then they both start at the same time. But, on [the atemporalist’s] view, my typing of this paper is simultaneous with the whole of eternity. Again, on this view, the great fire of Rome is simultaneous with the whole of eternity. Therefore, while I type these very words, Nero fiddles heartlessly on.
So according to AS,
1) If atemporalism is true, then eternity is simultaneous with every event in history.
2) If eternity is simultaneous with every event in history, then by transitivity, every event in history is simultaneous with every other event in history.
3) But every event in history is not simultaneous with every other event in history.
4) Therefore atemporalism is false.
Now this argument is valid. 2) simply appeals to the principle of transitivity, and 3) is evidently true. 4) follows by modus tollens. If atemporalism results in the notion that the burning of Rome is simultaneous with the Kenny’s writing, then atemporalism is to be rejected. But AS has not shown this to be the case: 1) is plainly false, for according to atemporalism, God exists, but He does not exist at any time. Hence eternity is not simultaneous with every event in history; indeed eternity is not simultaneous with any event in history. So then, when Aquinas uses the language of simultaneity to discuss the relation between time and eternity, he is only doing so analogically and not literally. The latter is required to make argument work, but unfortunately for AS it turns out, this is the very thing makes the first premise false.