I came here to exercise but it’s definitely not working. The gym’s owner keeps coming over to talk to me about God. He’s born again. He asked me what I’m listening to and like a fool I told him it’s a book about Darwin.

“Let me ask you this,” he say. “If we came from monkeys, why are there still monkeys?”

He doesn’t wait for an answer. Instead, he wanted to share his beliefs. It’s been fifteen minutes now and I’m not getting much of a workout. I’ve heard this all before, about how God listens to everything and can answer your prayers.  How can this guy claim to be such an expert on who’s listening? He doesn’t even notice that I’m not.

Bless his heart though, he hasn’t had my opportunities or education. I know that sounds arrogant but it’s true. And besides, if I can remember that, I have patience for him. Because the alternative, treating this like a mature debate about reality is only going to make me combative. His beliefs and those like them are hampering not progress, but long-range rescue efforts that could make the difference to whether our children live or die.

The last few pieces I’ve written here have been about the conflict between the Right to Believe and the Need to Know.  Like the gym owner, we all–bless our hearts–have the right to believe whatever helps us get through the night. And yet these days, in order to get through the crises we face, we need to keep fantastical beliefs from slowing and contaminating scientific progress.  Even without true believers throwing obstacles in the way, it is going to be very hard for scientific research to keep up with the crises we face.

I’ve argued that the only plausible resolution to the conflict between The Right To Believe and the Need to Know is for us all to take to heart what psychological research so strongly suggests:

We all believe untrue things that help us get us through the night. About those beliefs we have to cultivate an ability to say, “I believe it even though its not true. I believe it because it helps me, but I won’t try to make the whole world go along with me on it because on some matters, facing reality helps more. And saying this I can still take comfort from my beliefs, as though they were true.”

A few readers have commented that this is hardly plausible. I’ll grant that. Worse, it’s least plausible with the believers who are the most dangerous.  You can get a Unitarian to go along with that, but not a militant fundamentalist.

Still, the alternatives are less plausible. We will never collectively surrender to either pure science or pure belief. We cannot pretend that the last several thousand years haven’t honed scientific ways of knowing that really do put us more in touch with reality.  And we can’t pretend that those scientific ways have no bearing on our values and choices.

Sometimes the truth sets us free, and the truth here is that people cannot live by truth alone.  Life is short. Death is scary. The universe shows no signs of loving and protecting us from harm.  And we’ve got these amazing inventive minds. We are the first bi-mundial species.  Because of language we have the capacity to build elaborate imaginary worlds. This enables us to reference either the world we see and sense, or the world we believe and imagine.  This is our greatest gift and our biggest weakness.  On the one hand we can imagine a better world and then create it.  On the other, we can imagine that we are doing good when we’re really doing harm.  We can become convinced of untrue things, sometimes for better and sometimes for worst…all of us.

No one gets through life in strict adherence to reality. The burden is on each of us to find Optimal Illusions so that with the right blend of fantasy and reality we can get through both the dark night of the soul and the tough times ahead.

The conflict between science and religion should transition now.  Enough grabbing back and forth at the all-encompassing prize.  The prize must be split. Let science win the reality prize. All told, even with its fumbles, it does a better job of figuring out what is. Let religion and all other manner of revelation and wishful thinking win the comfort prize.

Then let’s transition the science religion debate into shop talk about how to divide duties between illusion and accuracy, faith and reason, hope and honesty, romanticism and skepticism.

For that to occur, the crusaders for science have got to stop pretending that they are somehow immune from believing untrue things.  They have to admit that the demand for both hope and truth co-inhabit all of us. Naturally, they won’t admit it if it means surrendering science’s authority as the best system so far for getting at what’s really true.

And the crusaders for religion, revelation, and wishful thinking have got to stop pretending that their way of knowing is as good as science’s at discovering what is really true.  Naturally they won’t if it means having to give up the comfort, joy and community they get from belief.

A few other readers said fine, suppose we could sit down to practical shop talk about how to manage the division of labor between science and faith. How do one pursue optimal illusion?

In the remains of this piece I’ll suggest a few angles for thinking about that wonderful and pressing question.

Who says?

Don’t take my advice on how to know whether an illusion will prove useful.  Or anyone’s.  Or, at least take it with this grain of salt.  We each answer the question under the influence of wishful and accurate thinking. The natural tendency is to say, “my beliefs are useful.”  So be especially skeptical about all that follows here.


One should always believe today what worked tomorrow, but since tomorrow isn’t here yet, we have to guess what that would be. There are no surefire recipes for deciding which illusions will pay off in the long run and which ones won’t.

There’s no way to know today for sure whether Google stock will go up or down tomorrow either, but the problem with optimal illusion runs much deeper than mere unpredictability.  Hope is, by definition an effort at a self-fulfilling prophecy.  Goethe said it well: “The moment one definitely commits oneself, then providence moves too. All sorts of things occur to help one that would never otherwise have occurred. … Whatever you can do or dream you can, begin it. Boldness has genius, power and magic in it. Begin it now.”

If it were that simple, all you would have to do is boldly hope, the universe would confer its genius, power and magic, and you would get everything you hoped for.

Not that simple.

Yes, the universe throws weight behind those who boldly begin things.  It has an escrow account waiting for the emboldened. But how much is in there is something we must guess at. I call it guesscrow, the unknowable quantity of momentum that you can unleash by hoping.  If the guesscrow proves sufficient, you’ll have achieved victory.  Your hope and wishful thinking will have proven extra useful. And if the guesscrow proves insufficient, the hope and wishful thinking will have proven extra harmful giving you momentum in a direction that didn’t pay off.

Visit opposing scenarios.

To figure out whether a belief will prove extra useful or harmful, make up mirror image scenarios. For example, on the question of whether religious belief will help or hurt our efforts to address climate change:

1. Looking back from the year 2040 we see that around 2010, it became obvious that esoteric religious law was a luxury we could no longer afford. With so many environmental imperatives we couldn’t afford to also impose a bunch of irrelevant imperatives that served archaic unrealistic beliefs.  As a result we abandoned fantasies, faced reality, exerted ourselves making rational sacrifices and save millions of lives that would have been lost if we dissipated energy on religion.

2. Looking back from the year 2040, we see that around 2010, religions, the only force in history able to sustain persistent international collective action, mobilized a movement  that saved millions of lives that would have been lost if we had abandoned religion.

In both cases, lives were saved, but in one by believing accurate, and in the other, inaccurate things.  Once you have your two scenarios, cleanly crafted to sound as plausible as possible, try to figure out which is more plausible.

For the big decisions, believe what you want, for the little ones, be accurate.

While there are no sure fire recipes for figuring out what’s an optimal illusion, there are some basic guidelines. For example, the division of labor should leave the little decisions to science:

A guy was boasting about his successful marriage.

“What’s your secret?” his friends asked.

“It’s a simple division of labor,” he said.  “I make all the big decisions and my wife makes all the little ones. For example, my wife decides where we live, where I work, where the kids go to school and what we buy. I decide whether the U.S. should pull out of Iraq.”

Illusion is best deployed on the big choices where verification is neither particularly pressing or possible. Facing reality is generally best on all else. We can rely on illusion for giving purpose to our lives, for thinking about the afterlife, for giving hope to the weak, young, old, or naive.  We can rely on reality checks for medicine, engineering, and social welfare.  In those climate change scenarios the motivations to address the climate crisis were different, but the technology deployed to address the crisis was a product of science not faith.

This is not just my personal recommendation. It is the tried and true method as practiced, with the rarest and strangest exceptions, even by the devoutly religious everywhere. They’ll say what they want about the unknowable, but they let science make the small decisions.

In the long run, accurate is better

The longer you live somewhere, the more likely it is you’ll have to face reality. If human life expectancy were a week, we might be able to get by believing we don’t have to look both ways when crossing busy streets. But living as long as we do, we need a more accurate interpretation of street crossing.

Collectively living for generations we are accumulating increasingly accurate stories. Religious ideas do get lost sometimes over the centuries, but accurate ideas rarely do. It’s as though humankind now recognizes that it’s going to be around a while, so it better make itself at home in the universe, accumulating accurate accounts of what this place is.

At the individual level, this rule of thumb suggests an amusing paradox:  If you only live once, you can get by believing anything, so go ahead and believe in reincarnation. But if you believe in reincarnation, you’ll live through many lifetimes, which means you better be more honest and admit there’s no reincarnation.

There are two kinds of real

Every belief that makes a difference is, in a sense, real.  Santa Claus is real in that the idea of him makes people spend billions of dollars in the fall. If, as a business owner, you didn’t believe in the realness of the idea of Santa Claus, you might well miss out on the revenue bonanza during the high season.  Likewise in some highly religious cultures if you don’t believe in the official God, your social standing and indeed your life could be at risk.  Philosophical idealists think this is the only kind of real we can rely upon.  Since we can’t know anything for sure about the real world, all of our ideas are real only in this manner.  The world is what we think it is, and the more universally and absolutely our beliefs are held, the more real they are.

There is, of course, another version of real. We could call it the universe’s habits. They push back against ideas that are not in accord with them, and they accommodate ideas that are in accord with them.  9.8 meters a second squared,  the acceleration rate of an object falling here on earth is real in a different sense from that by which Santa Claus is real.

The philosopher Charles Peirce argued that, with time the first kind of real comes to approximate the second kind.  That is, with centuries of human exploration we drop the ideas that cause the universe’s habits to push back, and we accumulate the ideas that are harmonized with the universe’s habits.  I agree, but also think that some of the universe’s habits are internal to us, and they need to be accommodated too.  A bi-mundial creature, who can foresee his own death, and who can imagine almost anything, is bound to make up some stories that conform more to the shape of his heart than the shape of the universe.  Evolution is not out to make you happy, but as a side of effect of what it did make you, it made you inclined to think it is.

Shedding light, lightly:

Which illusions are useful and which are harmful?  There’s no easy answer, but I sure would like to see the shop talk started.  I think an essential ingredient is levity.

My father, a scientific not a religious man with terminal cancer used to say “I’ll lick this thing if it’s the last thing I do.”  He would say it in a mock serious voice and chuckle a little. But he also meant it. He was hopeful and honest at the same time and he lubricated the friction between those two demands with warm self-effacing humor.