Altruism is usually understood as an act, that is of benefit for another person, at the cost of a sacrifice and without neither a benefit nor the expectation of a future benefit for the self, and that is a choice.
This kind of alleged altruism is typical for people with the particle identity. They interpret the behavior of others as altruistic, quite often they also believe their own behavior to be altruistic.
This is very different from doing a first beneficial step in a tit-for-tat strategy. Hyponanimalistic individuals attempt to find a balance of giving and taking without either taking advantage nor making sacrifices. They do not attempt to be altruistic.
But I am convinced, that altruism of the definition above does not exist at all. Even for those with the particles identity, every apparently altruistic act brings an adequate benefit to the actor. This benefit might just be completely inexplicable and invisible to others, because it may be derived from a delusion or innate instinctive urges.
I cannot think of any apparently altruistic act, that cannot be explained somehow as having hidden benefits.
1. There can be the delusion of a reward. Typically the reward is expected from the deity in the afterlife, getting a better reincarnation or such.
2. There can also be the paranoia of punishment to be avoided by the apparent altruism.
3. The act of apparent altruism can acquire praise, status, power and importance and it can add to the self esteem.
4. The apparently altruistic behavior can repair or enhance the self esteem by diminishing an incongruency between the perceived self and the ideal self. This could be in the case of amends because of guilt and remorse.
5. When someone's strong need to have a purpose is connected with a strong ought self, that requires altruism, the apparently altruistic act just serves to reduce the tension of the urge.
6. The urge to ensure the survival of the own genes is generalised to the survival of genetically related persons and to the entire ingroup, because the progeny depends on the survival of the ingroup. Apparently altruistic acts are just serving the survival of the own genes in a wider context.
7. Some apparently altruistic acts are not chosen, when the refusal of taking a risk would be punished.
8. Some apparently altruistic acts may be experienced instead as thrill, entertainment or rewarding in themselves in any other way.
