Very cool! Thanks! Of course, quantum theorists know that even "vacuum" isn't really empty... And even when it _is_ empty, weird things continue to happen: http://en.wikipedia.org/wiki/Aharonov%E2%80%93Bohm_effect At 05:57 AM 2/28/2013, Charles Greathouse wrote:

On the optimist vs. pessimist water glass, I like http://what-if.xkcd.com/6/

Charles Greathouse Analyst/Programmer Case Western Reserve University

On Wed, Feb 27, 2013 at 4:13 PM, David Makin <makinmagic@tiscali.co.uk>wrote:

...

To a realist - the glass is always full (of something).

To an opportunist - the glass is a free drink while the rest argue.

On 26 Feb 2013, at 23:06, Tom Karzes wrote:

...

I always liked this one:

To a pessimist, the glass is half empty. To an optimist, the glass is half full. To an engineer, the glass is twice as big as it needs to be.

Tom