[magicalhippo]

I heard something similar but in relations to soccer players and the goalie when taking a penalty shot: "do not hit the goalie!"

The point made was that it's impossible to not-do something, you can only do.

So when told "do not do X", the "not" disappears and it effectively translates into "do X". And so the soccer player being told not to hit the goalie ends up doing just that.

The moral of the story was to focus on what you should do, rather on what you should not do.

[scns]

This. The subconcious/animal doesn't get negation, we need to translate and try to do it with our conciousness/neocortex, which is pretty weak in comparison. Wasn't there a term like ego depletion? To many Nos over a day leaving no self discipline left at the end of the day? Same goes for should/should not, but maybe worse, if you don't/do do it (which you probably will) you feel bad afterwards.

Telling what to focus on works with kids, drunks and adults.