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What I Believe But Cannot Prove

June 2005

I believe, but cannot prove, that reality exists independent of its human and social constructions. Science as a method, and naturalism as a philosophy, together create the best tool we have for understanding that reality. Because science is cumulative, building on itself in progressive fashion, we can achieve an ever-greater understanding of reality. Our knowledge of nature remains provisional because we can never know if we have final Truth. Because science is a human activity and nature is complex and dynamic, fuzzy logic and fractional probabilities best describe both nature and our approximate understanding of it.

There is no such thing as the paranormal and the supernatural; there is only the normal and the natural and mysteries we have yet to explain.

What separates science from all other human activities is its belief in the provisional nature of all conclusions. In science, knowledge is fluid and certainty fleeting. That is the heart of its limitation. It is also its greatest strength. There are, from this ultimate unprovable assertion, three additional insoluble derivatives.

1. There is no God, intelligent designer, or anything resembling the divinity as proffered by the world’s religions. (Although an extraterrestrial being of significantly greater intelligence and power than us would probably be indistinguishable from God).

After thousands of years of attempts by the world’s greatest minds to prove or disprove the divine existence or nonexistence, with little agreement among scholars as to the divinity’s ultimate state of being, a reasonable conclusion is that the God question can never be solved and that one’s belief,
disbelief, or skepticism ultimately rests on a nonrational basis.

2. The universe is ultimately determined, but we have free will.

As with the God question, scholars of considerable intellectual power for many millennia have failed to resolve the paradox of feeling free in a determined universe. One provisional solution is to think of the universe as so complex that the number of causes and the complexity of their interactions make the predetermination of human action pragmatically impossible. We can even assign a value to the causal net of the universe to see just how absurd it is to think we can get our minds around it fully. It has been calculated that in order for a computer in the far future of the universe to resurrect in a virtual reality every person who ever lived or could have lived (that is, every possible genetic combination to create a human), with all the causal interactions between themselves and their environment, it would need 1010 to the power of 123 (a 1 followed by 10123 zeros) bits of memory. Suffice it to say that no computer in the conceivable future will achieve this level of power; likewise, no human brain even comes close.
The enormity of this complexity leads us to feel as though we were acting freely as uncaused causers, even though we are actually causally determined. Since no set of causes we select as the determiners of human action can be complete, the feeling of freedom arises out of this ignorance of causes. To that extent, we may act as though we were free. There is much to gain, little to lose, and personal responsibility follows.

3. Morality is the natural outcome of evolutionary and historical forces, not divine command.

The moral feelings of doing the right thing (such as virtuousness) or doing the wrong thing (such as guilt) were generated by nature as part of human evolution. Although cultures differ on what they define as right and wrong, the moral feelings of doing the right or wrong thing are universal to all humans. Human universals are pervasive and powerful and include at their core the fact that we are by nature moral and immoral, good and evil, altruistic and selfish, cooperative and competitive, peaceful and bellicose, virtuous and nonvirtuous. Individuals and groups vary in the expression of such universal traits, but everyone has them. Most people, most of the time, in most circumstances, are good and do the right thing, for themselves and for others. But some people, some of the time, in some circumstances, are bad and do the wrong thing for themselves and for others.

As a consequence, moral principles are provisionally true, where they apply to most people, in most cultures, in most circumstances, most of the time. At some point in the last 10,000 years (most likely around the time of the advent of writing and the shift from band and tribes to chiefdoms and states, some 5,000 years ago) religions began to codify moral precepts into moral codes and political states began to codify moral precepts into legal codes.

In conclusion, I believe but cannot prove that reality exists and science is the best method for understanding it; that there is no God; that the universe is determined but we are free; that morality evolved as an adaptive trait of humans and human communities; and that ultimately all of existence is explicable through science.

Of course, I could be wrong…

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17 Comments to “What I Believe But Cannot Prove”

  1. Paul G. Louden Says:

    I’m not a bumper-sticker fanatic, however, I could not resist this one:

    “Militant Agnostic: I don’t know and you don’t either!”

    It appears to me that to have a scientific take on the World is similar (say again…”similar”) view of most matters of fact.

  2. Roger Butters Says:

    Please forgive what may appear to be ‘nitpicking’.
    Where you use the words ‘believe’ and ‘belief’ I
    suggest that ‘assume’ and ‘assumption’ would be more appropriate.
    To me the verb ‘to believe’ implies a mental state
    incorporating ‘conviction’. For the very reasons you
    give, such ‘conviction’ cannot I think ever be
    justified. My suggested usage would emphasise the distinction which you rightly draw between your own
    mental attitude and that of other ‘believers’ – most
    particularly those who ‘believe’ in the paranormal and
    the supernatural. In addition it would also reinforce
    your final caveat.

  3. Felix Kaufmann Says:

    With all due respect, the defense of Free Will (desirable as it may be as a foundation of responsibility and ethics) by citing complexity and large numbers is a quibble. The conceptual conflict between predetermination and free cannot be resolved in that manner.

    A better approach would be the pragmatic one of saying that if what I write is predetermined, then it has no cognitive value. The basis of philosophy has to be the assumption of (at least limited, even if not absolute) freedom.

  4. Andy Walters Says:


    Consider the disastrous implications of truly “free” will. “Free” (from determination) implies, by definition and in the most absolute sense, unpredictable. A coin toss is commonly called “unpredictable,” but this is just a colloquial shortcut since it would be extremely difficult (but possible) to build a machine that, measuring key factors, could predict the outcome of a toss in midair. Free will, on the other hand, would have to be the sort of unpredictable that no predicting machine could be built for. If that were the case, the inexorable conclusion is that choices are random. Think about it: what is unpredictable is, by definition, random. And if choices are random, how can moral responsibility exist? How can we trust our own thought processes if random fluctuations are constantly being made?

    So I have turned your argument on its head and now ask you: if your writing is undetermined, unpredictable, and therefore random, how does it have cognitive value?

  5. Jack Davis Says:

    Although it seems incredible that man and the universe “just happened” it is also incredible to me
    that there was a creator that was not created by another creator. Either case seem equally likely but if there was a creator the big question becomes why. Was it so man could create 2000 different religions?

  6. John B Says:

    We don’t have free will, we have an illusion of free will. What we think of as free will is actually our decisions pre-determined by evolution and our upbringing, nature and nurture if you prefer.

  7. Ron D Says:

    When the subject of free will comes up, I always have a response that defines free will for me. If you think free will is true, then I suggest you drink a gallon of water and then choose not to go to the bathroom. Sure, its a simple thing and not very scientific, but it shows the difference between free will and the one thing we do have, freedom of choice. They are two different things, at least in my mind.

  8. Jim Castagneri Says:

    While I tend to agree with Dr. Shermers’ assessment of modern science versus the Divine (or faith perhaps), why is it that such postulates often evoke anger and distrust from the faithful? Those with alternate ‘faiths’ are often deemed tolerable while those who might be considered complete skeptics are heretics? Skeptics are an unpopular bunch.

  9. David Ferdinand Says:

    God?- we all simply do not know.
    We exist. The most distant opposite of that: nothing ever existed, did not occur. What the motivating force behind that original choice, conscious or allegorical, was, we do not now know. I feel that admitting to not knowing is more intellectually and spiritually freeing than simply saying that there is no God.

    The universe (matter, volume & physical laws), appears to be a vast machine that turns hydrogen into complete sentences. Whether these sentences are the end product or just another middle stage is yet to be determined.

  10. Sam Says:

    “Freedom is just another word for nothing left to lose”(song lyric), this suggests to me…a basic survival instinct for man to free…of course I may be wrong…but at least I’m free to make the observation! Or am I?

  11. John B Hodges Says:

    (JBH) Years ago I decided that the issue of “free will vs. determinism” is irrelevant to questions of ethics, and untestable with respect to matters of science. Since then I have tried to avoid wasting time on it. But it comes up every now and then in Freethinker circles, and many people are lured into arguing at length over it.

    Our ordinary practice is to ascribe “free will” to beings which are conscious and intelligent. “Conscious” meaning that they have an internal (“mental”) model of the external world, which they use to anticipate the consequences of different “imagined” courses of action. “Intelligent” meaning that their model is complex and sophisticated, and their imagination likewise, so they can find courses of action that will serve their purposes even in novel situations. “Free will” in such cases means that the great bulk of the IMMEDIATE causes of their actions lie inside their “skin” rather than outside, AND that their actions are not easily or reliably predictable by an outside observer.

    This use of the term “free will” does not require denying the hypothesis of “universal causation”, nor does it depend in any way on whether “causation” is always a single-valued function (i.e. whether the same inputs always produce the same output, or whether instead the output may be any of several values with some statistical probability for each.) In other words, this use of the term “free will” is fully compatible with “determinism”. Beings with “minds” sufficiently sophisticated to have “free will” may operate their “minds” deterministically.

    We assign “moral responsibility” to beings with “free will”, we assign praise and blame, rewards and punishments, to such beings, because that is the easiest (often the only) way we know to intervene in the causal chain. We want them to behave in one way rather than another, so we initiate some causes that we hope will have the effect of modifying their behavior. We hope they will include in their “mental” model that we will respond to their actions with praise/blame, reward/penalty, and that they will therefore “choose” a different course of action. The hypothesis of “universal causation” is irrelevant to this.

    If we gain some ACTUAL KNOWLEDGE of the causal chain affecting their actions, then we may intervene at a different place. For example, if we find that childhood exposure to high levels of lead in the environment leads to neurological damage that results in a lack of ability to control impulses, i.e. their ability to control their own behavior by “rationality” is impaired, then we may seek to reduce crime by banning leaded gasoline, lead-based paint, lead solder in water pipes, and so forth. But this is not the same as “determinism”, considered as a philosophical hypothesis.

    “Determinism”, the hypothesis of Universal Causation, says that “all events have causes; there are no uncaused events”. This is a universal claim. The critic may offer as a counterexample some event with no apparent cause. The believer in Determinism will reply “the cause may be unknown at present, but there must be one”. This is not something that can ever be proved or disproved, by any amount of evidence, short of complete examination of the entire Universe throughout all of Time. It is a starting assumption, a working hypothesis. Some have claimed that it is a NECESSARY assumption for the practice of science, but I don’t think so. Science can be practiced perfectly well under the assumption that many/most events have causes.

    So: I see no reason to spend one more second debating the question of “free will versus determinism”.

  12. Gareth Says:

    “I believe, but cannot prove, that reality exists independent of its human and social constructions. ”

    I think you probably can prove it, actually. It brings to mind the famous incident involving Dr Johnson’s and James Boswell leaving a Bishop Berkeley sermon questioning whether matter can be “proven” and Boswell asking Johnson how precisely he can refute Berkeley’s arguments…

    Johnson retorted “I refute it thus” and banged his foot against a large rock.

  13. Stephen Says:

    When the concept of evolution is critically evaluated, one can only marvel at the stupidity of the idea. It is intellectually absurd.

    Do not cloud the argument against evolution with alternatives to the question. Just evaluate it critically and objectively. Start with the pre “Big Bang” period. Where did all that matter come from? Can atomic particles evolve?

  14. Robert Elessar Says:

    I have similar thoughts to Mr. Butters’(response #2), but I have different specifc concerns though I agree with his quibble. I dislike the word belief, mostly because belief as generally used means the acceptance of something without necessarily having any strong evidence for it. I actually prefer the term “conviction,” unlike Mr. Butters, though I also like “assumption” the way he uses it. “Conviction” is related to the word “convince,” and a conviction implies, to me, that there was some degree of evidence behind it…though there can be many degrees of certainty, and even conviction that is truly “beyond a reasonable doubt,” is not the same as the proof of something in absolute principle. I think most of the things Dr. Shermer says he believes have a fair degree of evidence and reason behind them. The fact that reality exists outside human and social constructions may not be “in principle” absolutely proven, but if it doesn’t there are a LOT of strange implications and observations that need to be explained…and inductive reasoning suggests that it’s a lot more likely that the Universe was here before we ever happened than the alternative. For example. I could be hallucinating everything I’ve experienced since the moment I first became conscious, but that would have strong implications about just how good my hallucination machinery is, and would beg the question of just how I came to be there to be hallucinating anything.

    Similarly, though the “Militant Agnostic” bumper sticker IS very funny and makes something of a point, that point is overextended. Though we may not be able to say with 100% certainty (for instance) that a god doesn’t exist, we can try to estimate the probabilities AND can certainly explore something about what existence or nonexistence would imply about the Universe in which we seem to live, and about the characteristics such a god would seen to have. This can lead us to some pretty strong conclusions, even if they’re not absolute in the pure mathematical sense. I can’t say for sure that all the laws of aerodynamics are correct as we know them and I KNOW that our understanding of the laws of fluid dynamics is incomplete in principle, but I’m convinced that–barring mechanical failure–a huge metal craft of a certain common type can carry me through the air at dizzying speeds between two points thousands of miles apart safely and pretty comfortably. I have many times staked my life and the lives of loved ones on that conviction. So far so good.

  15. drachary Says:

    People dig to deep on simple matters. Free will exists. How did all of you get on here and write your comments. Of course, the universe has laws that we adhere to (I can’t fly in the air just because I want to). But that doesn’t mean I can’t choose to do what I want within the limits of those laws. It seems a lot of people say we DON’T have free-will beacuse we can’t fly like Peter Pan or we can’t piss out our asses. People need to get over the obvious(laws of the universe) and think within context!

  16. Gregor Schulte Says:

    Dear Mr. Shermer, Your weakest point is no.2. The starting claim that “scholars of considerable intellectual power for many millennia have failed to resolve the paradox of feeling free in a determined universe” suggests You haven’t read Schopenhauer’s “On the Freedom of the Will” yet. This essay would be a VERY valueable read for You because it resolves exactly the problem (perception vs. knowledge) cited above.

    Read the essay, it is likely to remove No.2 from Your list. (Or You can try to refute it – if You succeed in that task (very unlikely!), please email me how. :-) )

  17. Jonathan Says:

    History has a “provisional nature” so does ethics and art and others. I do not see how “science is separate from all other human activities due to its belief in the provisional nature of all conclusions.”