I read somewhere scientists ran experiments on hypnotizable subjects and observed their reactions when they made them think of only, in turns, the past, the present, and finally the future. Don't ask me how they could do that, but anyway;
when only in the past, they were sad and morose;
when only in their present they were all business, pragmatic, focused;
when only in the future they were giddy and thoroughly, unreasonably elated.
If true, sounds like living in the past is not a good place to be.
I think everybody judges everybody else all the time. It's automatic. How could you stop yourself from doing so, even if you could?
If you mean, judging others with unfair harshness while thinking yourself perfect? Would that make that person unhappy? I don't know. Maybe, maybe not!
True! We could turn that truth on his head and say happiness is living in the moment..
If one lives by past negative experience, then assumptions about the present might be negative. To judge others incorrectly, one is likely to presume to know more about them than one actually does know.
. . . nice sentiment, but in terms of critical thinking it is a logical fallacy