Value doesn't come from demand, quite the opposite. Some value should necessarily exist before to support demand. And the intrinsic value you refer to here is called utility, i.e. usefulness for achieving individual's ends. How on earth could value be intrinsic if it changes with people's preferences?
lets all agree that intrinsic is a synonym and means something that has utility on its own. these pedantic arguments are really annoying.
There is no utility existing on its own. Utility is always subjective and differs between people. In fact, even for one individual the utility of the same thing is different at different times (see
the law of marginal utility). If anything had utility on its own, no exchange would be possible at all...
I never said that utility of an object is the same for each person. However everybody needs to eat and drink. Thus food and water have utility for everyone. Nobody can do anything with
except dump it on the next guy. It has 0 value. You will agree with me once this pyramid collapses.