Is it naive to believe that the main goal of a person's life ought to be to achieve happiness (in whatever sense of the...

Is it naive to believe that the main goal of a person's life ought to be to achieve happiness (in whatever sense of the word you wish)?

What if an individual's idea of happiness is to bring misery to others, would it be justified?

Yes.

I should clarify. I mean to ask if the statement "the main goal of a person's life ought to be to achieve X" is naive for whatever specific X. Is it naive if X = pleasure? Is it naive if X = eudaimonia? etc.

It's naive if x= either an emotion or a mood. The pursuit of happiness is well enough, but only substantial goals will if not guarantee it, at least make it seem like an actual possibility.

yes

accept shame, cry, feel bad; makes you better

The naivety is not so much as the goal itself, or what you think one ought to do. I think you are naive for thinking there is a goal or there is something you ought to do. Not because goals don't ever come to us, but what you are saying depends on something else, so even if it is right, you can already tell what follows. What you are saying is relative to something else, which means it is engaged in some form of dialectics.

"People ought to be happy". Why? If it is better for them, then why do they "ought" to do it and aren't they doing it already? If not, why? You say you "believe" that is the case, but what do you mean by that? Do you trust that to be true? On what grounds? Do you like to believe to be so, or is it a burden but you believe it nevertheless? Do you know it to be so? Do you calculate it to be so? Do you think it is unknowable, but useful to think this way or is that too bold of a turn from your noble quest for truth for you to consider this possibility? Can anyone really "achieve" happiness? What comes after achieving happiness, does it last forever or does it ever end? When it ends, can we go back to it, how do we deal with this loss? Or if it doesn't end, isn't that somehow a scarier thought? You admit to the varying meaning of the word "happiness", but do you really think we are able to "wish" senses into the words we use? Does that happen because we independently blow meaning into its syllables? Or does that include the culture that surround us and mold language itself for us to use? If that would be the case, how does ethics enter into all of this if you acknowledge that our actions and words echoes in different ways into each other's ideas of what happiness is? Even if you know what happiness is to you, are there methods best or worst to reach it? Is there a pattern in why people choose to do one thing or the other? Is our sense of happiness set in stone or does it change over time? Is that what you wish happiness is what you actually believe or feel happiness is? Do they coincide?

You found a word, "happiness". But what of it? Trade it with any other word and you'd still have nothing but a bunch of questions to ask yourself further on. Try to define it and you'll end up with your own personal dogma. Try to open it up and you'll end up saying nothing. For a moment, think not in terms of things, objects, the content of a goal, think also in the structure of it, think of it as a position that can be filled with whatever else. You use the word "happiness" as a position. Because you say it can mean whatever I wish, so you are basically saying "the main goal is to achieve whatever you wish". It's not necessary to call it happiness.

cont

cont
What is most revealing though is that it appears you look for the goal, or "the main goal". After that is set we forget about it and go on asking "Is it happiness? Is it something else?" and so on, but why would there be a goal to begin with? Think again in terms of position and structure: if you have a goal, what do you have? I'd take it as something to aim for (not necessarily you'd reach it, just like you can aim an arrow to the moon and practice with that goal in mind), but then what would be the difference in aiming towards this or the other? Why happiness and not knowledge, or pleasure, or communism, or love, tradition, revoluion, or nothing or destruction or whatever?

Why does it have to be about a sentence that is universal, why aren't you talking about your own personal's goal in life in spite of what others are doing? And, actually, aren't you talking about that already? Aren't you dressing that up as universal so to reaffirm yourself and be able to sustain the expression of your desire? What are you looking for, anyway?

I think it is very naive to believe in a main goal. But I don't think there is anything wrong with being naive.
Just go on, user.

Depends.

If by happiness you mean joy. Yes.

If by happiness you mean satisfaction with oneself, no.