In a book that was released a few days ago, Sean Carroll, theoretical physicist, critic of religion, and former guest of The Colbert Report, presents what he calls the Big Picture. Neil deGrasse Tyson says the book “weav[es] the threads of astronomy, physics, chemistry, biology, and philosophy into a seamless narrative tapestry. Sean Carroll enthralls us with what we’ve figured out in the universe and humbles us with what we don’t yet understand. Yet in the end, it’s the meaning of it all that feeds your soul of curiosity.”
At salon.com, Carroll took part in an interview with fellow skeptic Phil Torres to discuss the book. At the heart of his work Carroll defends the naturalist worldview. What does that entail? According to Carroll:
Naturalism is the simple idea that there is only one world, the natural world; there isn’t a separate spiritual or theistic realm of existence. . . . Naturalists are atheists—they don’t believe in God—but the label is a positive claim about what one does believe in rather than what one rejects.
Every definition of naturalism has to face the problem of circularity. Defining naturalism as a belief that “only the natural world exists” is like defining God as “a divine being.” Unless one already knows what God is or what naturalism is, a definition that uses synonymous (or sometimes the same) terms as what’s being defined is unhelpful.
Carroll claims the label of naturalism is a positive one about what does exist (the universe) rather than what does not exist (God). But, as Carroll points out in the interview, naturalists disagree over what constitutes a part of the natural world. Some naturalists say immaterial realities like minds, math, and morality are illusions and don’t exist. Other naturalists say they really do exist but in an immaterial way.
The only thing on which all naturalists agree that is unique to naturalism is that God is not natural, and therefore God (and probably angels or other spiritual beings) does or do not exist. That sounds more like a philosophy defined by what it lacks instead of what it contains.
Carroll says in the interview:
I talk a lot in The Big Picture about Bayesian reasoning. To some set of competing ideas, we assign a “prior” credence (roughly, the probability we think each one might be true), then update those credences as we gather new information. It’s crucial that our credence in a given idea never go all the way to precisely 0 or 1, because that means that no new information could possibly change our mind about it. That’s no way to go through life.
While Bayesian reasoning can be very effective, it doesn’t make sense to say there are no statements that have a 100 percent chance of being true or false. People couldn’t even have reasoned conversations with one another without acknowledging self-evident truths of logic like the law of non-contradiction, which holds that there is a 0 percent probability that a statement can be true and false in the same time and in the same way. This is also important when discussing whether God exists, because God is a necessary being; on a Bayesian scale, the probability he exists is 1.
That doesn’t mean the existence of God is self-evident (which is why St. Thomas Aquinas did not subscribe to Anselm’s ontological argument), but it does mean that if the evidence shows God exists, then this is a necessary truth about reality and has to factor into our description of reality as such.
Carroll’s interviewer tries to take the place of the honest lay believer and asks him “[if] every effect has a cause. If the universe is an effect—which one could certainly argue that it is—then what caused it?”
“It’s not true that every effect has a cause,” Carroll replies. “That’s just a convenient way of talking about certain features of the macroscopic world of our everyday experience, one that is not applicable to how nature works at a deeper level. . . . There’s certainly no reason to think that there was something that ‘caused’ it; the universe can just be.”
This seems to be a reference to the fact that some interpretations of quantum physics hold that there can be indeterminate and so “uncaused events.” But that is not the same thing as saying that something like our universe can come into being from pure nothing. (I addressed this objection here a while back). One also can’t say the universe, which didn’t have to exist, can “just be”—that doesn’t answer the question of why there is something rather than nothing (I address this question in chapter 8 of my book Answering Atheism).
The interview ends with Carroll answering the interviewer’s question about how life can have meaning if the universe will eventually collapse into a state of maximum disorder and all life will perish. According to Carroll:
The fact that life is temporary is precisely what does give it value. Why should we care about a century-long existence if it was followed by an infinitely long span of additional existence? We are fragile, ephemeral, finite creatures, bringing meaning to the world around us through our understanding and our care. Our lives have meaning exactly because they are all we have, and therefore are infinitely precious to us.
First, the idea that value comes from scarcity applies only in some contexts. It’s true that natural resources are valuable when they are scarce, because the demand outstrips supply. But other things retain their value no matter their abundance. Virtues like love, courage, or compassion don’t become less valuable as more and more people practice them, for example.
Second, Carroll misunderstands the question when he says our lives have meaning because “they are all we have.” When people ask, “What is the meaning of my life?” they don’t want the pedestrian answer, “A series of interconnected conscious experiences and relationships that are embodied within a single person.”
Well, yeah, we know that. What we mean is, “What is my life meant for? What is the purpose of my life?” If atheism is true, the answer is: nothing; your life is a meaningless accident.
The famous twentieth-century atheist Bertrand Russell honestly embraced this depressing truth:
That Man is the product of causes which had no prevision of the end they were achieving; that his origin, his growth, his hopes and fears, his loves and his beliefs, are but the outcome of accidental collocations of atoms; that no fire, no heroism, no intensity of thought and feeling, can preserve an individual life beyond the grave; that all the labours of the ages, all the devotion, all the inspiration, all the noonday brightness of human genius, are destined to extinction in the vast death of the solar system, and that the whole temple of Man’s achievement must inevitably be buried beneath the debris of a universe in ruins--all these things, if not quite beyond dispute, are yet so nearly certain, that no philosophy which rejects them can hope to stand. Only within the scaffolding of these truths, only on the firm foundation of unyielding despair, can the soul’s habitation henceforth be safely built.
Of course, there is much more that I can say on these topics, but I will adjourn for now. I just received my copy of Carroll’s book, so keep an eye out for a future critical review of it.