Value in Relation to Scarcity

If you were to ask a person hundreds of years ago "What's worth more a pile of gold or a pile of salt?" Most people would have taken the pile of salt in a heartbeat.
Gold is a wonderful thing and very nice to look at, but you cannot live without salt. When salt was more scarce than gold, it was valuable enough to use as a currency itself. The term "salary" is related to the Latin for "salt". Today, of course, salt is almost worthless. If you were to pose the same question to an average person today, almost every person would take the gold in a heartbeat. You may ask yourself, "Why is this?"
Well to put simply, salt is practically worthless. There is less of gold around when you compare it to salt and therefore gold is more valuable. Because gold is scarce it has greater value when compared to salt. Scarcity, it seems, has a great deal to do with value.
This is something that you should never forget. A wonderful way to make a profit is by trading in something that's scarce. This may not interest you very much although you should never forget the value of scarcity.