Let's start with the definition, since the word is oh so full of emotional baggage. From Wikipedia: "Selfishness is placing concern with oneself or one's own interests above the well-being or interests of others." Right then, fairly straightforward. How did this word acquire such a negative connotation in our culture? Who cares? Let's try a mental experiment and universally eliminate selfishness and see what happens to the world, shall we? Surely, it will be paradise on Earth, right?
In your mind, you may imagine an action like a mother sacrificing herself to protect her infant son from bullets with her body as an example of a selfless act. I would argue that the animal instinct behind that action knows nothing of ethics. It's an evolved behavior - those whose ancestors were more likely to have their offspring survive no matter what are the ones whose genes fill the the world today. The selfish genes guide that action. Does that technically fit under the definition of altruism? Sure. Am I impressed? Not really, because I don't believe that in this particular instance there's much conscious decision making involved.
But where were we? We want to eliminate ALL selfishness. Some people think it's moral to be altruistic, and the best test for morality is universality. I.e. "do not murder". What kind of a world would we live in if everyone followed that edict? A pleasant one.
So let's do that instead of looking at our selfishness-ridden world today. Let's make the the lack of self-interest and selfishness universal and take it to its logical conclusion. Here we stand, in a world where the interests of others are always to be placed above our own. It's our world, tomorrow. Everyone has just woken up with this realization: what others want is more important that what I want. Nobody can be selfish any more.
Neither you, nor I can bring ourselves to eat anything. We are not starving, but millions of people are. We immediately ship the food to the poor of Africa. However, they don't want to eat. They feel like they are a burden to everyone and they just wish to die peacefully so as to not inconvenience anyone. Our convenience is more important to them then even their own life. But then, their well being is more important to us than even their own wishes. Also, there are more of us and we have advanced weaponry. The first military invasion with the intention to force-feed ensues thereafter. The poor of Africa commit suicide en masse before they can be seized to be fed and cared for.
There are 5 people at the hospital who need kidney transplants, and now there is a million people outside who want to volunteer. After all, the donors have no concern with their own well being, inconvenience, or pain any more. But guess what? Now the patients don't give a damn either - the potential donors' welfare is more important to them than their own. Way more important! How exactly do you resolve this dilemma? The overwhelming mob of donors restrain, drug, and incapacitate the patients and force the transplants in them. That's right after they hold a lottery where the winners get to donate their kidneys.
The rich go to the banks and withdraw all their money. The fractional reserve banking system collapses. All lenders forgive all loans. All borrowers chase around the lenders trying to FORCE them to take their money. The former rich walk around the streets with bags of cash and beg people to take it. The people don't really want it, though. The former rich are desperate, they argue that they REALLY want the poor to take the money more than the poor do not want to receive it. Begrudgingly, the poor agree. They go to stores to buy stuff that they really don't want (since they have no self-interest, just to make the rich feel better), but the shop owners won't accept the money because everything is now free. People want to work all day to produce goods and services for others, but others want no goods and services at all to make sure that nobody has to lift a finger, or spend a day at work away from their family. Nobody is really happy.
Students now want to study as hard as possible with no consideration for laziness or other selfish interests to please their parents and teachers. Teachers just want their students to be happy, and relax. "I just want you to be happy. No, I want YOU to be happy." MORTAL KOMBAT!
What meanings do the words "want", "freedom", "charity", etc have in a world without selfishness and self-interest? None. How can you want what's good for me when I want what's good for you and nothing for myself? There is no want. How can you be charitable when the people you want to help have no interest in being helped for their own sake? There is no charity. What free will can you imagine when your own desires are always secondary to those of others and the collective? There is no freedom.
What an untenable, unethical, and profoundly evil clusterfuck of a world. Keep calm, and stay reasonably selfish!*
*Limited scope offer only! Acts of charity not included. Helping people because it makes you feel like you are living a fulfilled and meaningful life (while making a difference in the world by helping others) not included. Helping your loved ones because you evolved to do so and fully expect reciprocity not included.