Is nihilism the logical extreme of atheism?

[genkaus]

As Genkaus correctly points out, failure to find a solution to nihilism doesn’t make it false, which would be an argument from ignorance.

Come again? I don't recall doing that.

At the same time, no one cannot justify saying they have a raison d’etre (if it matters to them) without having some way to ground the meaning of their life with three basic concepts: purpose, lasting value and significance. As I see it, atheism undermines all three. And without that solid foundation, all atheists are tacit nihilists no matter how adamantly they deny it.

The keywords here being "As you see it". That is insufficient to establish your views as logical.

Does one's raison d’etre doesn't require all three - purpose, lasting value and significance - or any one of those would suffice or are there no other possibilities such as duty or obligation? Secondly, the idea of lasting value is subjective for now, since you've failed to define how long value should last or why it should exceed one's lifetime. Thirdly, and most importantly, you have to establish atheism is sufficient to undermine all three and would not require any congruent philosophy.

To establish your view as logical you have to justify these points, otherwise all of it is simply "as you see it".

To me, the truly honest atheist is one that accepts existential absurdity. When I was an atheist, I found myself able to counter the occasional moments of despair with a pleasing noble defiance of my fate, that “rage against that dark night”; the myth of Sisyphus; Zarathustra’s dancing; and all that sort of heady stuff. But there is nothing wrong with simply focusing on the mundane, just getting on with getting on, and “enjoying the ride.”

Again - "to you". For your view of an honest atheist to be accurate, you have to establish that existential absurdity is the only logical conclusion of atheism - which means establishing that every other worldview is either self-contradictory or implicitly accepts existence of a god.

One of the actual joys of atheism is defining your own purpose in life.

Not necessarily. You can be an atheist and
- believe the whole point of being a biological entity is to propagate genetic material and consider your purpose to have as many children as possible.
- believe in certain immutable laws governing conscious entities and believe your purpose to live according to those laws.
- believe you owe your parents your existence and feel obligated to allow them to define your purpose.
- believe your existence to be impossible without your society and feel obligated to accept the purpose that society has defined for you.

All of these options involve as much choice and self-defining as accepting whatever purpose you believe your god has ordained for you.

Such joy is an emotional response that doesn’t rationally counter nihilism. When someone defines purpose as that outcome towards which something is directed, then they are invoking Final Cause. Atheism, per se, does not exclude final causes, but the reduction of the world to purely efficient causes acting on material bodies does. Therefore ‘purposes’ are illusions born of viewing higher-order processes that are fully determined at lower levels of order. So while it would appear as-if intelligent agents have goals, in actuality there are no final ends and it is irrational to speak about any life having purpose.

First of all, you are confusing reductive materialism with atheism again. Atheism does not entail the belief that world is "purely efficient causes acting on material bodies".

Secondly, even that belief doesn't imply that the higher-order processes are illusory. Software is completely determined by lower-level events within the hardware - that doesn't make it an illusion. The conceptual nature of things like "purpose" or "goals" doesn't make them any less real than "atoms in motion" they are the result of. Which is why, there are final ends in actuality and it is rational to speak of life having purpose.

When people talk about a life’s purpose they usually are thinking of a higher criteria that just goal-seeking behavior and final ends.

Are they?

What they really mean is that their life counted from something, i.e. their life has, or will have, lasting value.

Vague generalization. The criteria for considering is your life "counted" is subjective. Which means "lasting value" would be subjective as well.

Value requires that someone appreciates and desires something which is valued. The value of life for the person living it, seems self-evident, since all other valuables require already having a life. But because life ends, the lasting value of a person’s life depends on their life having continuing value to those remain alive and future generations. Then the sun blows up and with it any value our lives once had. Thus at a bare minimum, for human life to have value there must be some enduring agent to whom human life is valuable.

Why would you equate value with lasting value and then lasting value with ever-lasting value?

Where one's raison d’etre is concerned, life having value to the person living it - something you regard as self-evident - should suffice. Why should that value then stretch beyond his life? Your reasoning here seems to be "that is what people generally mean when they talk about value of life" - but that is not a sufficient reason.

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We know that natural life is unjust. Taking away heaven and hell limits God to imparting justice in our natural lives, which would conflict with natural laws.

Why would it conflict with natural laws?

Yes. In my understanding, atheists operate on the premise that there is no ultimate justice, as that's the natural order of things. Reality. So an atheists morals are based upon an unfair system. The Christians morals are based upon a fair system, therefore our moral standards are different.

Wrong on three counts.
- Atheists can believe in natural justice . That is, justice is inherent in the natural order of things.
- Disbelief in any natural or ultimate justice system need not be the basis of morals. In fact, once you realize that there is no ultimate or natural system to dispense justice, you have to build a fair system if there is to be any justice in the world.
- For most of the Christians I encounter online, their morals are based on the belief that actions are irrelevant within the system (faith, not works) and infinite punishment/rewards based on finite lives. That is hardly a fair system.

There can be none; that purpose is defined by a deity, and is inherently subjective, just as any morality derived from the same source must be.

(my bolding) That seems contradictory.

Its not.

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How is it subjective? I either know Gods will it I don't.

The objective purpose is justice. That's not negotiable.

Justice, within your theology, is subject to god's will - whether you know it or not. Thus, the purpose dependent on subjective justice is likewise subjective.

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Yeah, that's the part that never gelled with me either, when apologists start bandying the word "objective" around when talking about their god; god is a subject, just like anyone else.

Its a simple fallacy of equivocation. By "objective", people mean "independent of any being's wishes, will, opinions or desires". Apologists take that to mean "independent of any human being's wishes, will, opinions or desires".