Siobhan asked
What is the Philosophy of Time Travel?
Answer by Jürgen Lawrenz
This reminds me of a story, Siobhan, of many stories I’ve read from centuries, millennia ago — Orpheus in the Underworld, Odysseus, Gilgamesh, the Pharaohs — Cheating death, cheating time, flying through the air with magical animals, descending into the bowels of the past, tearing off the dark cloak from the future… so many dreams that will not die. Now we have science fiction to drape them — Science! Wow!
Yes, there have been philosophers too, in the middle ages, who propped up these dreams and stories with cast-iron logic, but we don’t believe them any more because we found that some terms in their syllogisms, called ‘common notions’, were not common any more when the power of the Church began to wane. Today we have science. Science delivers; we believe in it. Nevertheless, doubts creep in sometimes. Just how much science is there in science fiction? I suspect: very little; though a plethora of fancies that could be so construed on the basis of superficial similarities.
On my understanding, we owe our current conceptions of time and space to Einstein. His theory is called Relativity. It does not make provision for time travel; but is on the contrary, totally and absolutely inimical to it. So you see the problem: Relativity has to be proved wrong before one can philosophise about time travel. No philosopher would risk reputation and career on such a fool’s errant.
What about quantum theory? Don’t experimenters sometimes find particles veering off the straight and narrow path into the future to jump into the past? Well, that’s one reason why empirical physics and particle physics don’t get on, why we don’t have a ‘unified field theory’. This ‘maybe time travel’ might be nothing more than a limitation on our observational powers. But even if particles truly bounce into the past sometimes, they are not ‘things’ and therefore we can’t get a ride on them. It doesn’t stop fiction writers and movie makers, of course. Our imagination is fuelled by such fancies.
Coming to the end, you would not expect to be the first person to put a question of this nature to the panel. So let me finally point you to a more detailed rendering of the problems of time travel that I wrote in these pages a few years ago and is still accessible from the archives of Pathways. Happy reading!
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