Fair point, but it doesn't really affect the sense of what I said in my original comment.

Also, just because economists haven't found a bright line between concepts doesn't mean they aren't distinct. I think there's a distinct difference between needing food, and wanting an xbox.

If you start with that assumption, you immediately confront the issue that you may 'need' food, but you don't need tasty food, or much food, or even "easily digested" food. One does not even 'need' "clean" food, as humans are easily able to tolerate being ill most of the time; and, unfortunately, many people worldwide operate with this constraint their entire lives.

In fact, we didn't even really 'need' food at all: what we needed were a few nutrients, maybe in the form of a pill. Food is a luxury, and if our stomachs disagree we can always get stomach-ectomies.

Until, of course, you find that one guy who defines the point of his existence to be the very first guy to get a billion points in Halo: a person might be in a hospital, dying anyway, and while eating may prolong his life another month, he will consider his whole existence to be a waste if you take away his Xbox; at this point the concept of objective needs totally disappears, and you end up back in the land of "differently elastic demand curves".

I didn't say everyone's needs are the same.

Ok: I think one easily gets the other impression from your want/need distinction. Regardless: the first two paragraphs do not even touch on that: that person might 'need' an Xbox, but not one that has a working blue video composite. The point is that there is an elasticity to the demand curve for everything that the person might 'want', but there is no obvious breaking point where you suddenly end up with a 'need': and a great example is that you do not really 'need' food, you just want it very very badly.

That's fair enough. I think this explains the reactions of others in this thread. The distinction between want and need isn't important to my original point, and I certainly wasn't intending to claim them as objective. It was a careless choice of words.