Making your mind up

There was quite an interesting discussion a few weeks ago on Free Will
vs Determinism but it died a death, at least in part due to the
departure of some contributors to the Land Beyond GG. I'd like to take
up some of the issues again if anyone is interested.

One point made by Hemidactylus that didn't get developed any further
was the way that we sometimes give a lot of time and effort into
making a decision - he gave the example of buying a car. It's also
common for someone to want to "sleep it on it" before making a
decision where the decision is important but it is not clear what
decision is best. If a decision is essentially predetermined then what
is the point of that time and effort or sleeping on it?

Tied in with that is our ability to change our minds after we have
made a decision - has determinism some convoluted way of working that
predetermines what way we will make a decision but also predetermins
that we will change it?

A reminder that in the Libet experiments so beloved of determinists,
there was no precursor activity found in regard to making *major*
decisions or changing one's mind so how does that fit in?