Altruism - We are programmed from birth

     Altruism is defined as  ‘acts that intentionally benefit another organism, incur no direct personal benefit, and sometimes bear a personal cost’. This definition resonates a lot better with our intuitive sense of altruistic behavior. And unlike the more ‘biological’ or enforced type of altruism, this type  is completely voluntary, without the threat of punishment as an inducement to act.

The Limbic System in the brain is responsible for, among other things, the sensation of pleasure, reward, and the feeling of well-being. One of its important projections is to a group of neurons deep in the brain call the nucleus accumbens.

This nucleus mediates such diverse pleasurable sensations as optimism, food, sex and recreational drugs. In fact, in this nucleus resides the anatomical location of drug addiction.
After all, ask any volunteer in a soup kitchen and she will tell you that she derives enormous satisfaction from her good works.
Ask any biologist and he would likely volunteer the explanation that, just like food and sex, altruism is associated with a sense of pleasure because ‘it is good for us’-- ‘us’ meaning our species.

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