Rod Speed wrote:

Tim Watts wrote
Rod Speed wrote
Mark wrote
The Natural Philosopher wrote
Bernard Peek wrote:
The Natural Philosopher wrote
Bernard Peek wrote
The Natural Philosopher wrote

Well thats uyouir knowelege limits and I have mine.

I know.

Let's say that if anyone has broken in they have
left no trace and altered nothing. Or I would *know*.
Which makes it 'not compromised'

Absence of evidence is not evidence of absence.

Hint: there is no such thing as an undetectable change.

I'd like to see evidence for that assertion.

Are you really stupid?

I'm a philosopher. I was hoping that you knew something that I didn't
and I could learn something. It seemed improbable given the ignorance
that you appeared to be displaying but hope springs eternal.

If a change makes no difference to anything, ipso facto,
it is not a change. All changes therefore must make a
difference, and are therefore detectable.

Yes, but as I pointed out in the post to which you replied absence
of evidence is not evidence of absence. You can know that you
haven't detected a change, but you can't know that there is no
change. Absence of a change is not detectable.

It is.

It would be theoretically possible to hide any change if you
had the resources and opportunity. For example if you use
hashes to detect changes then someone could alter the hashes.

Not if they arent on that system they cant.

You can reduce the risk of this happening but it will always be 0.

Nope. Its perfectly possible to have a risk of 0.

Even against aliens with telekinetic abilities?

Yep. Any change they make that matters will be detectable.

And as you cannot prove such aliens don't exist, I suspect your risk is
0 even if you bury your computer in a concrete block inside a metal box.

You're wrong.

Nope - I don't accept an exactly 0 risk is possible on any non isolated
computer. Very close, perhaps, but not exactly 0.
--
Tim Watts