I think that the idea from FMA is pretty shallow in itself. It states that something of a certain VALUE must be given up to gain something else of an equal VALUE. Yet, how does one go about determining this VALUE? The Value of things is not a universal standard. Value itself can be based on several different things such as emotions, monetary value, historical importance, etc. For every person, the value of certain things amounts to something else and the whole idea of value becomes relative. If this is the case, then every character in FMA must have their own approach to alchemy. Not everyone needs to give up the same things to gain something else. Then, there must be a huge number of ways in which to gain the same thing. Hence the equivalence of two things also becomes a relative property. Then how does one look at equivalence in the universal scheme of things.

(I can't believe i just brought relativity into the whole thing! What am i doing in this thread anyways??)