Well said, @lukestokes
I've always liked to debunk the idea of 'intrinsic' value with this little scenario:
Imagine if you were marooned on a desert island via a plane crash - with no real hope of rescue anytime soon - what would be more valuable to you? The 15 gold bricks you happened to find in a treasure chest - or the 15 lbs of potatoes you managed to scrounge from the supplies in the plane wreck? Of course it's the latter.
As you said, value is entirely subjective - it's just a question of the situation one finds themself in. (ie. Supply and demand will always reign superior, no matter what.)
Great analogy. I had potatoes for dinner tonight with lovely melted cheese. I’d defiently pick the potatoes. :)
By the time I hit my teens, I learned to never doubt the delicious taste of a potato with melted cheese! :-)