Earlier quoted context omitted.
What purposes exactly? If you'd ask me those derivative products are a convenient alternative to casino style gambling and mostly add instability to the market. I would love to hear an informed opinion, though. What do these products solve, why are they essential? Also, what would happen if we would tax them more heavily, perhaps incrementally over a period of time?
Options and many other derivatives are not merely a casino game. Their unique role as financial instruments is to allow the transfer of risk from those who have risk and don't want it (hedgers) to those who don't have any risk and do want it (speculators). This is different from gambling because gambling by definition involves the creation of entirely new risk for the purpose of wagering; derivatives transfer pre-exi…
However, I still don't see the necessity of these instruments.
For example, wouldn't it be more natural for a pension fund to just spread the risks by buying different stocks?
Also, I'm not convinced that derivatives would decrease instability. Like I said, I would guess they do the opposite.
Perhaps there is some theory that can show this (something akin to e.g. the fact that passive systems are always stable, for some definition of "passive"). Or perhaps there exist empirical simulation-models that can shed a light on this?