falsifying the idea of falsification

[Belacqua]

It can still be true. It just can’t be demonstrated.

And statements which can’t be demonstrated don’t have a lot of utility.

‘In a cave on a planet 1000 light years from Earth, natural processes have carved an astonishingly accurate facsimile of the words “Boru Was Here” (in Sanskrit) on a rock outcrop that resembles a rudely shaped turnip.’

The above statement may be true, it may be false. But since we obviously can’t go and look, the statement is worthless. What are we supposed to do with it?

Boru

I think if we make your example a little less specific, it will demonstrate the difference between falsifiable and unfalsifiable.

If we say "such an inscription exists somewhere in the multiverse," this is unfalsifiable. Because the multiverse is a big place, and it's impossible to check everywhere.

However if we say "no such inscription exists anywhere in the multiverse," this is falsifiable. Because if we found such an inscription the statement would be falsified. 

What's at issue with falsifiability is not whether we practically will be able to find such a thing. It's that in principle the statement could be proven wrong.

Likewise no serious person expects the theory of evolution to be falsified. It is as proven as something can be. But we know in principle how it could be falsified -- by finding a rabbit from the Precambrian era. If it is possible in principle to show something is false, it's falsifiable.