I've thought about this before and i think the problem is this:
The (lower)Middle class has to spend a lot of time worrying about paying the bills, the mortgage ,and generally just managing the little money they have, on a daily basis . Because they are preoccupied with making ends meet, stressing about their car breaking down, about being late, about burglars breaking into their houses,etc. they have less time and energy to concentrate on things that are TRULY important in life:
Like Family(and/or Love), Friends, Leisure, success,etc.
---->
Having money to pay ALL the bills BEFORE they are due, having a safe/comfortable/fast car, having money to install state of the art security/surveillance systems in their homes, having a comfortable house with lots of entertainment(be that a pool,jacuzzi,home gym,pool table,plasma tvs,whatever) eliminates MOST of the above mentioned problems/stress factors....
So, the guy that's better off doesn't have to worry about all this petty bullshit and is able to concentrate on the things that TRULY matter, which equals a higher level of happiness.
I'd say if you're a down to earth person, who was happy to start out with, and manage to stay that way after hitting the point after which you don't have to worry about petty bullshit anymore, yes, money will make you happier.
But if you were unhappy to begin with and expect to just *BUY* happiness....make sure you stay on top of your game and STAY rich...cuz once you go broke, you'll lose
1. the hot 'girlfriend'(or wife) who was only with you because you had money
2. the toys you bought to make up for your unhappiness
3. the 'friends' that only hung with you because you had money to blow...
