I've studied econ at the graduate level at MIT after having taken it as an undergrad as well, and I have a degree in Finance, so I didn't mean to imply that I don't know what I'm talking about. But I know a lot of other topics as well and I've always objected to terms of art in one field being easily confused with terms from other areas, and hell if I can remember what an inferior good is 20 yrs later. My point was not that you didn't know what you were talking about; I joined in because between the two of you I replied to, I didn't think your discussion was benefiting the rest of HN as much as it could because many of those people have not taken any econ at all. I was trying to Econ 100 the discussion, without losing the flavor of what is interesting about Giffen goods; and I think that if researchers are going to "prove" that Giffen goods don't exist in aggregate (<-- not Macro term of art), they need to also address the obvious short term circumstances (as I tried to describe) where it's clear that the underlying principle is actually operating, whether it has an effect on market clearing or not, because people can go one extra week without meat, just can't do it forever.

Not trying to argue, just trying to clarify what I came upon. Econ theory I think is sound but requires many simplifying assumptions to teach and learn, and then when we talk about whether Giffen good actually exist or not it's easy to lose track of simplifying assumptions like "long term" or "substitution".

cheers.