One of the most mutually beneficial states that two people can achieve is symbiogenesis, where they take such pleasure in each other's happiness (and displeasure in each other's unhappiness) that they start viewing each other's interests almost as their own. The more strongly this happens, the closer the pair is to being a single, two bodied organism, working towards a common set of goals.
One remarkable benefit to such a state is that it allows for a level of optimal allocation of resources ...
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happiness
Planning Your Life Based on Your Ideal Ordinary Week
When people consider how they want their lives to be, they often think in terms of reaching specific milestones. They set goals like earning a certain amount of money, achieving a certain level of success at work, having a certain group of close friends, falling in love, getting married, having a spectacular wedding, having children, and being thought of as a good person. But milestones like these don't necessarily determine how much people enjoy their lives, how high their mood is on a regular ...
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