Daniel Kahneman explains that perception (and consequently our perception of happiness) includes an experiencing self and a remembering self.
Consider going on a wonderful date - you have three hours of fun and enjoyment then at the very end you get in an argument. In all likelihood you will remember the whole evening as “bad” even though you really experienced several hours of “good” and only a few minutes of bad.
Memory and moment-to-moment experience are rather different. He references a study where participants were told to hold their hand in ice water for a few minutes. Group A held their hands in the water for say 5 minutes. Group B held their hands in the water for say 7 minutes but for the last 2 minutes researchers warmed up the water slightly. It turned out that Group B reported the experience as less painful and unpleasant than Group A. But hold on — they actually experienced 2 more minutes of pain than the first group right? Well because the ended was not so bad they remembered the whole experience as not so bad.
This speaks to the fact that often the experiencing self and the remembering (or reflecting) self are often at odds.
When it comes to happiness — these two selves operate rather differently. We can think of it as being happy in your life versus being happy with your life. Being happy in your life consists primarily of moment to moment experiences: fun, positive emotion, flow, and being around people we like. Being happy with your life consists more of achievement, social comparison, and meaning and purpose.
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