This can be clearly shown by comparing two different lives, but with those same happiness, one is leaning upward over time to increase happiness throughout their lives. Other lives are constantly leaning downward. Happiness is equal, but the first person's life seems more satisfying. There is always good expectation in the future, things are always getting better. The second situation is that things continue to tilt downwards, but to remember the joy of the past happiness.
There are many thought experiments in hedonism. Among many things, one of the interesting experiments I found is The Experience Machine. "Experience Machine" created by philosopher Robert Nozick in his works "Anarchy", "Country" and "Utopia" is a beautiful thinking experiment for the world of virtual reality. The Experience Machine is a scene that Nogic seeks to imagine a machine that can give people an ideal and enjoyable experience. This experiment is based on the premise that humans have found a way to stimulate the human brain and induce a fun experience that can not be distinguished from reality. Then he asked if he / she likes the machine better than the reality machine, if there is a choice?
A recent philosopher, the late Robert Nogic, has developed a well-known "experience machine" thinking experiment. And it revealed what we want in addition to subjective and enjoyable experience. In Anarchy, State and Utopia (1974), Nozick convincedly suggested not inserting a machine and doing fun simulations because he wants to do something in some way. Please touch the real world. Clearly, we want more than just superficial enjoyment, our judgment on society far exceeds the source of this pleasure.