Do you agree with me that lack of knowledge of probability coupled with a lack of common sense is a key driver of poverty across the globe?



Just to highlight the fact without exhaustively qualifying my statement, I will give a few examples:

  1. Hyperbolic discounting refers to the tendency for people to increasingly choose a smaller-sooner reward over a larger-later reward as the delay occurs sooner rather than later in time. When offered a larger reward in exchange for waiting a set amount of time, people act less impulsively (i.e., choose to wait) as the rewards happen further in the future. Put another way, people avoid waiting more as the wait nears the present time. Hyperbolic discounting has been applied to a wide range of phenomena. These include lapses in willpower, health outcomes, consumption choices over time, and personal finance decisions.
  2. People often end up gambling excessively because of incorrect and unfounded beliefs. Unfortunately, the poorer the neighborhood, the higher the risk for problem gambling, according to a study from the University at Buffalo Research Institute on Addictions (RIA).
  3. People wait for luck to give them success.
  4. etc


René Descartes once said, “When it is not in our power to determine what is true, we ought to act according to what is most probable.” Now, I’m not sure whether or not I agree with that statement, because I’m not sure whether it is in our power to determine what is most probable.




But Wait, What Exactly Is Probability?

But what does probability even mean? The classical definition of probability, according to Pierre-Simon Laplace (yes, that Laplace):
The probability of an event is the ratio of the number of cases favorable to it, to the number of all cases possible when nothing leads us to expect that any one of these cases should occur more than any other, which renders them, for us, equally possible.


The Implications of Probability

But back to what Descartes said. My question is simple: When can probability truly be applied to real life?

We apply probability a lot more than we think. In fact, every time we say something is true, we are really saying it has a 100% probability of being true. When we say that the Earth’s gravitational pull is (close to) a certain number, we mean (in frequentist terms) that the relative frequency of the limit of that number is 1. We generally assume that time will not effect the probability of certain statements or truths, including scientific propositions; in fact, one foundational truth of science is that accurate results in the past are still valid today. There is a 100% probability the laws of nature do not change. (Or is there?)

In general, I don’t really mind this use of probability. It’s pretty effective for what it attempts to do: to predict. But the predictive number we assign to a statement does not in the least affect its actual truth value.

Consider the classic example of probability: a deck of cards. Assuming the deck is sufficiently shuffled so that the cards are distributed randomly, the chances of drawing a certain card are 1 in 52, or approximately 1.92%. But that’s not really true! That’s just the best prediction we can make. The truth is, there is exactly one deck of cards arranged in exactly one order, so there is a 100% probability that a certain card will be drawn and a 0% probability any other card will be drawn. The reality is that there is no chance. As David Hume said, “Chance is only our ignorance of real causes.”

This raises another question: Is there irreducible randomness in nature? Is radioactive decay really random, as Schrödinger’s cat might suggest? Are there hidden variables? If there are hidden variables, probability is merely a concession either of a lack of data or of an inability to analyze the data. But if quantum mechanics is truly random, or indeterministic, what exactly happens? (I’m asking rhetorically.) How does a physicalist metaphysic (How ironic is that phrase?) explain randomness when science depends upon an orderly universe? Imagine if Newton’s second law were “f = ma only at random times.” But if the universe is deterministic, from whence (I love that word) do the independent relationships arise?


Probability and Belief

Descartes attempted to apply probability to entire belief systems, and so do a lot of people today. Atheists (who sometimes exalt themselves as “skeptics” or “brights”), in particular, argue that the existence of God  is exceedingly improbable. (By the way, I don’t like to think of things this way. I don’t think of atheism as not believing in God and theism as believing in God; I think of them as beliefs in different sets of independent truths, that actually aren’t all that different. More on that at another time.) But where are the numbers? How can you evaluate the probability of  God? If God’s probability is either 0% or 100% (He either exists or doesn’t exist), are we going to say it’s at 7.3% or 50.01% or whatever? Should we only believe in God if His probability is greater than 50%?

And what factors affect the probability of God’s existence ? That is itself a question that is rarely asked. I’m still not sure how to answer it.

Even assuming that physicalism can explain the entirety of our existence, does that automatically bring God’s probability to 0%? Recall that probability requires more than one trial. We only have one trial of the universe, so we can’t determine God’s probability at all; we don’t have enough trials. True probability cannot exist outside the context of a sufficient number of trials. Thus, even in this (hypothetical) atheistic utopia of a universe, God might still exist. His probability would be unknown. Which is why agnosticism makes a lot more sense.

But consider more specific questions. Are the New Testament documents reliable? Can we really assign a number to the probability that they are reliable? Should we assume that every piece of evidence has equal weight? How does this work?

The reality is that people who consider their answers to such questions “objective” are overstating the precision of their arguments. Prominent atheist Antony Flew recently converted to deism because, in his mind, the existence of God became more probable than the non-existence of God. While I’m happy a prominent atheist has renounced atheism (though he’s far from Christianity), I still think this whole idea is kind of absurd. At what point did the existence of God top 50%? Which tidbit of evidence did that? Did Flew assign numerical values to the different facts on each side and weigh them up? Or did he just use what atheists rarely admit to using, a gut instinct?

We cannot rationally calculate God’s probability. There is no such thing. We can examine evidence, but our final determination will be arbitrary and subjective, even if it is based on objective and truthful information. Which is why people disagree more about this than about whether or not 2 + 2 = 4. (It does.)



Does that mean we should all be agnostic? No! (I don’t think so.) It does mean that reason is not the only source of knowledge in this area. And it means that our question should be rephrased. “What is the probability that God exists?” should become “Is God compatible with what we know about reality? Is physicalism compatible with what we know about reality? Are they both?” (That would be interesting.) And finally, we must ask what role pure reason plays in this all. (Hint: I don’t think it’s 100%.) (Get it? I referenced probability in my parenthetical comment!) (Three parenthetical comments in a row!)

God is more than a hypothesis.

Source: Partly from

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