My theory is that what we humans call happiness may actually lie in ignorance. If you suppose that posessing more information will put additional burden on one's psyche (knowing that a tiger is aiming for you specifically out of all of the herd is infinitely more stressful than just knowing that the tiger is aiming for the herd in general. Even better is not being aware that a tiger is out on a hunt at all), then better off people have more things to warry about courtesy of their fortune (they have more assets/information to warry about).

At the same time a well off person is happier than a poor person in absolute terms bcz he can afford more enjoyment of life (he can tickle his senses with more toys), but each additional unit of enjoyment delivers everdeminishing unit of bliss (law of deminishing returns), while his warries increas at a constant rate. Hence the illusion/perception of being unhappy, and one's illusion/perception is his reality. The fact that he cannot fully share his perception with a fellow human creates the myth of him being happier in the observing crowd. He may be able to relate (successfully transfer) his illusion/perception through sustained/constant interaction, which explains how families come to share similar world views & mood is contagious.

Is this not just a tangent to the main point about investment though?  Is the purpose of investment to make one happy in the first place?  The purpose of investment is to make one feel more secure, nay, be more secure.  A net result of knowing that you are in fact more secure is that you will have the freedom to be happy.  We are all a part of these larger "investments" in many facets of humanity.  Belonging to a nation state is an investment.  You'll contribute to this nation in some way in exchange for a degree of security.  Wherever the state has less influence, the much more hazzardous life becomes.  Wild animals, bandits and simply having to provide for yourself is a stressful existence.  I do not argue that one cannot be happy in such a situation but I would say that one has more freedom to be happy with a level of security.  Losing family members to disease, wild animals and even bandits does not contribute to one's happiness.  While investments and therefore security may give one the freedom to find happiness, one does not necessarilly find it but the option for its pursuit is there. 

The other question is, is the purpose of life to find happiness? 

There is no ultimate purpose to life. Life just is. If you, as an individual, choose to make something the purpose of your life, then that something becomes the purpose of your life so long you continue to support the idea or continue to exist.

In your assesment of investments you are overlooking the existance of risk. Risk of an investment is multiplied when that investment is represented in easily transactable/transferable entitities (not sure if that is a proper term for it) such as money. Purpose of money is to facilitate asset transfers, side effect being that it also makes the risk (posibility of loss) easier too.

Exactly! Muk have you read Sapolsky's "Why Zebras Don't Get Ulcers?" Are you an academic? If not, you oughtta be!

ADDIT: and Jerm, you are right about "happiness" being hard to define, even within the parameters of one fairly consistent "culture," let alone across cultures. That is where multi-disciplinary folks like myself who like to check to see for corroboration between multiple different measures (psycho-physiological, health, social, psychometric, behavioral). The science of studying happiness or well-being is frankly still in its infancy: reason being, the dogma that has persisted (as I pointed out above) since the Renaissance that material wealth = happiness/well-being.

Ironically, this idea has grown as religious notions of happiness in an afterlife have waned, and as ideas of happiness from being a patriotic member of a tribe has also ebbed and flowed.

I find it fascinating to read about people's personal lives in the 18th and 19th century. It is remarkable to hear about what it was that made them "happy." Granted, what we have to read are the records of the exceptionals more than the averages, but . . . what I notice is that we have got more petty, self-interested, shallow, uncritical, non-reasoning, tribal, lazy, undisciplined . . .

I would argue that it most definitely is NOT a tangent to the initial question Muk posed. This is because, another way of looking at publicly traded stocks is not as a constellation of free moving entitites ruled entirely by their individual free will, and acting rationally in their own self-interest, but instead as a system that intrinsically favors the uber-powerful, and intrinsically exploits the rest.

Lets face it: the majority of us have very little real influence in what happens in the stock market. Collectively we might, but then each of us has only a very tenuous influence on the collective actions of all of us peons. In contrast, the Warren Buffets of the world have power equivalent to Ancient World Monarchs. If Buffet wants a particular thing to occur on Wall Street, he very well may have the actual agency to make it happen by virtue of strategic buying and selling.

Putting it this way, the "purpose" of investing is not to serve the interests of the hundreds of millions of little guys, but to serve the interest of the few score big guys. Put in that perspective, we should not be surprised if plenty of little guys (at least half?) wind up getting more displeasure from their investing activities than pleasure.

My point about whether happiness is the purpose of life is to point out that even if investment doesn't make one happy per se, and happiness isn't the end goal, there is great value in investment.  That is, happiness isn't the only reason one should invest.  I also disagree that there is no general purpose in life.  I'd argue that contributing to mankind is at least one purpose of life (at least one that secular and religious peolpe can agree upon ).  People find purpose when they believe they are contributing.  Whether they are or not is something each individual needs to figure out.  Investing is one way of contributing. 

Yeah Scip, kinda like voting for the President of the USA, no?

No, never read his stuff, although I might have come accross his ideas in my various readings. No I am not in academics, not professionally.