Easy Questions?

[Swatopluk]

http://www.halbmikrotechnik.de/service/chemie/fluessig/federweisser/bilder/fw-gaer-tech.jpg

Of course one should use cork not rubber for the plug.

[Bob in a quantum-state-of-faith]

There is it!  Straight out of a 17th or 18th century lab, too.   

[Aggie]

Oh, I'm trying to get it to finish by Christmas.  That's why I want to stop fermentation.  I've also got some heavy 1.5 L Grolsch bottles with a wire bale that can take some pressure, if I want to keep any carbonation in it.  I'm aiming for liqueur; not sure if you can carbonate syurp.  Then again, I suppose that's what Coca-Cola does.

[Sibling DavidH]

You can put some sodium metabisulphite in to stop it, that's what I always used to do.  Not much or you'll taste it.  As for airlocks, they're very cheap at any wine-making shop - over here, anyway.

[Aggie]

I've taken far too much chemistry to want to actually put it into practice (biology was closer to my heart, but not mind).

I made it up to ~20% sugar, and will keep an eye on it.  It tastes really nice, like bokbunja ju.

[Pachyderm]

Will be bottling the first attempt at cider shortly...

[Swatopluk]

By what process do we note the absence of something?
Is it just by comparing a mental image with what we actually see and noting a difference?

[Griffin NoName]

This is a quantum question and should have a quantum answer.

[Aggie]

By what process do we note the absence of something?
Is it just by comparing a mental image with what we actually see and noting a difference?

It must be, no?  If one doesn't expect to see something there (or at least consider the possibility that something could be there), one couldn't note an absence.

[Sibling DavidH]

Swato's suggestion is surely right.  If you look at a place where you have reason to expect something to be, and you note its absence by the fact that you can't see it when conditions are such that you should be able to, then you have reason to believe that it's not there.

Of course, for 'see' you may substitute 'hear', 'feel' or whatever.

We had a friend with very little sense of humour.  When it was foggy and you couldn't see the hill to the west, we could always wind her up by telling her that it had disappeared, or been stolen.

[Swatopluk]

Related question: Why do we so often think that something is missing, although it is not and the object presumed missing is right in front of you?

[Sibling Zono (anon1mat0)]

Missing from your current mental model I would imagine. You expect it to be somewhere where it isn't according to your immediate perception, which as you should know, isn't completely reliable.

If one doesn't expect to see something there (or at least consider the possibility that something could be there), one couldn't note an absence.

There is a philosophical vs idiomatic question there, are unicorns absent from my home? With 'missing' the word necessarily implies that the object in question exists (or existed).

God may be absent, but is he missing?

[Sibling DavidH]

Related question: Why do we so often think that something is missing, although it is not and the object presumed missing is right in front of you?

Because we're dozy buggers, not to mention getting old.

[Griffin NoName]

Related question: Why do we so often think that something is missing, although it is not and the object presumed missing is right in front of you?

When I've lost something in plain sight it is usually a different colour or shape/etc from my mental picture of it. I am usually cross when I find it: surely I should be pleased?

[Aggie]

Related question: Why do we so often think that something is missing, although it is not and the object presumed missing is right in front of you?

I agree with Griffin somewhat; it's largely based on search image.  I think we fail to see something right in front of us because we assume that since we're looking for it, it must be obfuscated. The brain obliges our assumption.