Richard asked:

1. Is it logically possible to travel backward in time and live in a former era? why or why not?

2. Is it logically possible to make a robot (a mechanical device composed of inorganic materials) that
can think, feel, and act like we do? Is it physically possible? why or why not?

3. In his book The bible and UFOsLarry Downing claims that the miraculous events recounted in the
bible were actually caused by space aliens. is his claim as reasonable or more or less reasonable
than the claim that god caused them? why or why not?

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The answer to Questions No. 1 and 2 is 'no'. The answer to Question No. 3 is: science fiction is not
science.

Let me pursue No. 3 first. God is not science fiction. It is a metaphysical concept. Whether or not you
believe in it, is your business, but you might like to consider the following: There are four ontological
proofs, at which various highly educated and sharp-witted thinkers have tried their hand, including
Anselm, Descartes and Leibniz. Kant thought he disproved them all. Perhaps. But of the essence to
Kant's disproof is the further recognition that certain matters of human cognition are simply not
provable: there is room for doubt. For example, if such a concept as God is describable in a logically
coherent form and (say) a computer program written with all possible variables does not hang up,
then the concept is sound. Kant's disproof in effect boils down simply to stating what earlier
philosophers had (maybe deliberately) overlooked: that a proof (or a computer programme) does not
necessarily confer existence. Big difference.

So the belief in an all-powerful God as the source of our universe is not an irrational belief, just
unfashionable. Some scientists like to put 'infallible' arguments abroad, and in particular all manner of
proofs based on materialistic considerations, but these fall necessarily into the same bracket as
Kant's disproof. You can't prove that God exists; but from the puny evidence we possess of how the
universe actually functions, it is not possible to construct a waterproof argument for the contrary
supposition. As Leibniz truly said: the necessary (logically unimpeachable) truths are so few you can
count them on the fingers of your hands. Everything else is contingent. But anything you know only
contingently is at best a reasonable assumption. Just as Kant said.

Now where does this leave Mr Downing? I would say in Fairy Land. I'm pretty well read in this kind of
literature myself; it fascinates me. But when you close such a book, your brain should come back to
life. The fact is that not a single shred of evidence has ever been produced, nor a single cogent
argument ever been proposed, why any stories or artefacts from ancient days could not be explained
by the presence on Earth of a higher civilisation of, say, the Sumerian type. Maybe Atlantis was real?
I'd be willing to consider it. At least you don't have to go fossicking into outer space.

Question 1 is difficult; probably more difficult than most of us realise. We are so brainwashed these
days by the copulation of light with time that we forget what kind of human artefact time actually is.
Again: there is no incontestable proof that time exists. Photons may be emitted in a quantum
experiment and observed to be travelling backwards in time. But this is theory: and in the theories
which apply to this situation time is either 'renormalised' or the particle admitted to be more than one.
Either way, you cannot hitch a ride. More importantly, the only logical argument for time travel ever
produced that has any merit at all was Godel's. Einstein was horror-struck by it and repudiated
without stopping to think. However, Godel's point was: in a universe where this is possible you would
have to leave nearly all your current cosmological theories at home and most of the advanced
scientific experiments we perform routinely nowadays wouldn't work.

You realise, I hope, that this is a huge domain, where everyone has different opinion. But I think
everyone who argues for, if they were prodded really hard, would have to admit that, in the end, none
of the knowledge we possess today permits time travel. It relies totally on extrapolations of unproved
extensions of relativity and quantum cosmology. Indeed you ought, perhaps, to read Julian Barbour's
book on The End of Time.He makes a good case that time is a fiction. Point blank.

Other than this, the same question is often asked and the Pathways contains a good database which
you should check out. There's even a discussion by myself, where I produce more arguments against
it, from a different perspective, in the middle of other people arguing for it. So a very democratic
database, worth reading.

Finally No. 2. Keep asking for proof. Anyone who tells you 'yeah', shift the burden of proof onto their
shoulders. Because there is a short answer. The only thinking+feeling+acting that occurs anywhere in
the universe, as far as we know, is connected to biological fibres. There are good reasons for this
stress on 'biological': feelings are obviously connected to nerve fibres; but in fact it is no different with
thinking. So the whole idea of a robot with feeling+thinking+etc. is at bottom nothing more than a
pretence: the 'Frankenstein syndrome', as I like to call it, humans fancying themselves at 'playing
God'. It is also the pretence, not backed up by any sufficient scientific reason, that the products of
thinking+feeling+etc. are portable, e.g. that you can take them, like the contents of your CD and copy
them as data to another.

Jürgen Lawrenz

Sydney