Does atheism preclude the possibility of eternal happiness?

No.  The vast majority of God's human children shall spend eternity happier than they ever thought possible.  Evil people will just not be as happy as good people.  Atheists?  there are all kinds.  Jesus promises to reward us according to our works, not our beliefs.

We don't know. We do know that God loves atheists exactly as much as He loves Christians. We do not know how He will deal with those of His beloved children who are ignorant of Him.

Atheism does not include, or preclude

Atheism is just the absence of theism.

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Regards,

John Popelish

Life and the nature of the universe preclude the idea of eternal happiness.  But limitless happiness right now?  That is achievable in small flashes.

Yes. If one sincerely believes that there is not god, then God's kingdom will be off-limits for them, unless they repent while yet alive. 

No one gets eternal happiness.

Atheism is one and only one thing: not believing in gods.

No, the nature of humanity does that. In order to give a human eternal happiness you would have to modify them to the point that what remained would simply not be human.

Entropy is the over-rising veto proof force that all matter will eventually succumb to. Even if every conceived medical miracle occurred the human is still physical and thus will one day prove that it is not eternal.

A non-physical human, a being of pure thought with no body...well we have no evidence that such a thing is possible but assume it is.

Your non-physical human would have no ability to form new memories. Even if they could only remember a single thought in a million years eternity laughs at that. Gradually your non-physical human would have so many memories that sorting them would be impossible. You have seen people in their 90s struggle, what about a human in their 10s of millions?

Your non-physical human would have no senses. Our senses are physical. He/she would be deaf, touch less, blind, without taste or smell either. Even if somehow non-physical sensors were added the non-physical human would have no ability to interact with the physical. He/she could perhaps see light (somehow) but not move an object.

Which brings us to the next point. What gender does our non-physical human have? Gender is a physical biological thing.

Tell me if you found a being that had no senses, no ability to exert their will, no ability to form memories, no gender, no organs would you really point at that thing and say "that is a human"?

I didn't wake up one morning and decide to be an atheist.  I was raised in a christian home, but after years of not getting answers, and learning about philosophy and world religions, I came to the realization that I simply didn't believe. I see it more as an arrival at a conclusion than a conscious decision. I rarely debate the existence of god; I find debating the nature of belief to be much more interesting.

Belief isn't something you can turn on and off like a switch.  You believe, or you don't.  When challenged, I ask the person making the challenge to decide to not believe for a few weeks.  They can't, anymore than I can simply decide to start believing.  With that in mind, if there is a god, then presumably,  that god created me, and wired me in such a way as to instill a lack of belief. Seems weird, but it is what it is.  

On the other hand, I know the value of being a good person.  I don't lie or steal, I treat other people well, and I help a lot of people out.  So if I'm judged on my actions, I think I'll be fine.  If I'm judged on my beliefs, it doesn't strike me that I'm deserving of punishment, as this is what I am, an atheist.    

It does and Christianity also doesn't include it.