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(I love a good analogy and despise a bad one. This post is about two unforgettably eye-opening analogies, neither of which includes babies or bathwater, and both of which can help kids grasp an otherwise ungraspable thing: how recent is our arrival in the universe. My next post will look at the unfortunate seductive power of the bad analogy. That’s where you’ll get your wet baby.)

When I was ten, I knew the universe was really, really, really, really old, and that we had only been here for a small part of it. The unarticulated picture in my mind was of universal history as a half-hour TV show, with humans arriving during the second commercial break saying, What’d I miss? What’d I miss? (I picture the Universe rolling its galactic eyes, saying Oh, nothing. Couldn’t very well start the party without baboons. Ooh, hey everybody, the baboons are here! Let purpose commence!)

I had the sequence right, but the proportions were cartoonish: the Big Bang bangs, stuff congeals, life appears, dinosaurs, cavemen, Greeks, Columbus, me.

Then came Carl Sagan’s Cosmic Calendar— and suddenly, vividly, I got it.

Compress the 13 billion year history of the universe into a single year, starting with the Big Bang on January 1 at midnight and ending in the current moment, midnight on New Year’s Day the next year. When did humans appear in the past year? Sometime in the summer, maybe? Fourth of July weekend good for you? That seemed about right to me at age ten.

Even that was progress compared to the biblical version, of course, which at this scale pops humans into the mix ninety seconds after midnight on New Year’s Day, before the last of the noisemakers has even stopped bleating. But even at July 4th, I was still a full paradigm shift away from getting it.

Sagan took care of that in three pages of The Dragons of Eden, and in the process blew my hair back in a way that I wouldn’t even want to recomb.

When you boil 13 billion years down to one, each day is thirty-five million years long. We all have days like that. The Milky Way galaxy forms around May 1st. The Earth is born on September 14th. So for the first two-thirds of the history of the universe, our planet didn’t even exist.

Humans can be safely considered unimportant during this eight-billion-year period.

Life on Earth appears just half a billion years after the planet itself, on September 25th. No, not dinosaurs. Microscopic, single-celled life. They rule the Earth with a tiny iron flagellum until November 12th, when minuscule undersea plants appear. By December 1st, these plants have created an oxygen atmosphere.

For us, you’re thinking, deep inside. They’re getting the world ready…for us. You’re funny. Stop it.

Ready for dinosaurs now? Keep waiting. Thirty-ton lizards do not spring into being from microorganisms. There’s work to be done, and this kind of work takes time. By December 16th – just eight shopping days until Christmas – we’ve reached a critical step on the road to Us.


By December 19th we’ve got fish. Not yet grillable, but stay tuned. Land plants thirty million years later on the 20th, insects on the 21st, amphibians on the 22nd…

Wait a minute. Surely I’ve made a mistake. Only nine days left in the year, and still no Lords of the Universe?

On the 23rd, the first trees come to pass. And at last, on Christmas Eve, the dinosaurs begin their 180 million year reign. Christmas Eve. December 28th, wham, an enormous asteroid slams into the Yucatán. Also flowers are invented.

Oh, and humans? Lemme check.

Okay…here it is. On the scale of a single cosmic year, your species – Homo sapiens, was it? – okay, Homo sapiens enters at 10:30 pm on December 31st. That’s ninety minutes ago. Ninety minutes out of a year.

That’s Finding Nemo with one potty break.

The Pyramids were built ten seconds ago. The birth of Christ was four seconds ago. Copernicus, one second ago. So much for the grand human pageant marching across the span of all time.

Richard Dawkins has another spectacular time-grasping analogy. Stretch your arms out to represent the span of the history of life on earth. Now this is not even the whole history of the universe, mind you, just the last quarter of it, the time since life began on Earth just over three billion years ago. You’d need three other people standing to your left with arms outspread to represent the universe prior to life’s emergence on Earth.

From your left fingertip all the way across your middle to well past your right shoulder, life consists of nothing but bacteria. At your right wrist, the most complex form of life on Earth is worms. The dinosaurs appear in the middle of your right palm and go extinct around your last finger joint. The whole story of Homo sapiens is contained in the thickness of one slim fingernail clipping.

As for recorded history – the Sumerians and Babylonians, the Pharoahs of Egypt, Ancient Greece and Rome, Jesus, Napoleon and Hitler, the Beatles and George W. Bush – they and everyone else who lived since the dawn of recorded history are blown away in the dust from one light stroke of a nail-file.

Feeling special?

99.98% of the history of the universe happened before we arrived. You cannot maintain a worldview in which we are the central actors without utterly disregarding that fact. And a fundamental premise of the three Abrahamic religions is that humans are the universal Main Event. Try to make the New Testament work without that idea. Or the Old, for that matter. It all falls to tatters in this context.

We don’t have to indoctrinate our kids away from religion. We really don’t. Theistic religion is a round peg in the square hole of reality. But fortunately for religion, most folks tend not to put too much effort into seeing reality clearly — which makes it much easier to kinda sorta still force that round peg into place. Powerful analogies, carefully applied, can form a relatively effortless bridge between us and otherwise ungraspable concepts. Several great ones appear in the pages of Parenting Beyond Belief, and I’ll include more in upcoming blog entries. Use them to help your kids discover the honest depth and breadth of our remarkable reality and they won’t even go looking for a place to put that silly round peg.

Once their hair is blown back by the real world, they’ll toss that peg over their shoulders with a yawn and never look back.

Dale McGowan is chief content officer of OnlySky, author of Parenting Beyond Belief, Raising Freethinkers, and Atheism for Dummies, and founder of Foundation Beyond Belief (now GO Humanity). He holds a...

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