Too much greed is bad and too little greed is also bad, we all need greed and most of us have it some more than others.
Greed is good, because it is the most important incentive for people to work hard, get a good education, start a business, or invest in a company. This makes people productive and contributing members of society. And in return, people are paid a salary, become more educated, and (hopefully) build wealth so that they can in return live a prosperous, more comfortable, and full life.
Unfortunately, this leads to three types of bad greed.
First, after some people have collected a large enough personal wealth, they retire. Thus making these people no longer a productive member of society, who use more resources than they provide. Sure, these people invest their wealth in stocks, bonds, real estate, and other financial investments; however these people are selfishly idle when they could still be contributing more to society. Of course not every retired person is able to work in the traditional sense, but they are still able to contribute. For example, instead of playing golf with other retirees in Florida, retirees could help their children by babysitting their grandchildren or even teaching their grandchildren how to fish or knit a sweater. In other words, it is alright to retire from work but do not retire from society. If someone is physically and mentally able to contribute, do so.
A second form of greed is for people to continue collecting wealth even after they have far surpassed the amount of money that they need for the rest of their lives. Some people leave so much inheritance that even their children and grandchildren can not possibly use all of it. This is why some people, such as Bill Gates, his wife (Melinda Gates), and Warren Buffet are donating most of their huge fortunes to charity. They understand the virtue of generosity, instead of succumbing to greed.
Third and finally, greed sometimes drives people to do unethical, immoral, and illegal things in the pursuit of more money. This is the greed that we find "evil".
Greed is typically considered the accumulation of wealth for personal satisfaction. It has no useful purpose except to become rich and to continue getting more wealthy. It is a strong desire in each and every one of us that is extremely difficult to overcome. Only through continuously contributing and donating to society can we find true rewards that are far greater than the illusion that greed provides.
How can we spread the greed? Take from those who have too much and give to those who have too little?