You may not believe it's possible to define the meaning of life in a short essay. So, let's do the impossible, or strive to. How hard could it be?

On the broadest possible scale, what is the universe doing? By long confirmed observation, the universe appears to be moving from a state of low entropy to one of high entropy. The universe is expanding. Stars are burning hydrogen. Weather wears down mountains. People mix cream with their coffee. 

How does life contribute to this universal tendency which we call the second law of thermodynamics? After all, life would appear to violate entropy, making copies of itself, evolving new forms, growing to wonder about its place in the universe?

According to Caltech cosmologist Sean Carroll, the purpose of life is to “hydrogenate carbon dioxide.”

Say what? Well, there are many, many reactions that go toward increasing entropy in the universe. Burning is one. Rusting another. One is when hydrogen combines with carbon dioxide to make methane. Well, when hydrogen tries to combine with carbon dioxide to make methane. It tends to get stuck making formaldehyde instead. But methane has more “disorder,” so to produce the most entropy, this reaction needs an efficient way to put in energy on a local level, skipping the formaldehyde to create methane.

Life does that. So much so, that if we detect methane in the atmosphere of another planet, that world more than likely harbors life. (Methane, doing its best to help with entropy, breaks up quickly through other chemical reactions. So, if you can detect it over interstellar distances, there’s a lot of life doing a lot of living somewhere.)

Life then is just a temporary bit of complexity on the way to a universal state of higher entropy. In the same way we might build a complex rock crusher if we needed to crush all the rocks in the universe to dust. We’d crush all the rocks, and then eventually the rock crusher would rust away. Entropy always wins.

OK, you probably thought I meant the meaning of “human life,” and that I would be talking about a higher purpose that goes toward making our endless striving and suffering worthwhile.

Does the universe have anything to say about that? 

I think it does. Compared to us, the universe is big. Unimaginably big. As Douglas Adams wrote in The Hitchhikers Guide to the Galaxy, “You just won't believe how vastly hugely mind-bogglingly big it is.”  If a star were a grain of sand, the next closest star to us would be nearly 20 miles away, and there are more stars in the universe than grains of sand on all the Earth’s beaches.

And everything we’ve ever heard of; every name we’ve ever known, every god, prophet civilization, and soothsayer whose story has lasted through the centuries, every great leader and unforgettable entertainer; the totality of all and everything we know is an imperfect bit of history limited to of our own wet grain of sand, lost in the cosmic dark.

Pilot Officer V.A, Rosewarne, a 24-year-old pilot killed in the Battle of Britain, had this to say: “The universe is so fast and ageless that the life of one man can only be justified by the measure of his sacrifice.”

Now there’s some meaning.

Rosewarne, like you and me, lived a life of striving and suffering, though his suffering was too great and his striving too short. 

We all strive and suffer, hope and despair, love and hate. Both the person you love most in the world and the one you hate with all your being suffer in the same ways you do, experiencing the uncertainty, the loss, the doubts and the fears.

Around us, the universe is largely indifferent to our existence. It is not built to nurture us and keep us safe. Before life, Earth was a volcanic hell, without oxygen and bathed in ultraviolet radiation. Earth was never perfect for life. Life made Earth livable. It’s the biome that nurtures us, not the rock. Life terraformed a planet and brought Sapiens into being.

It could be said then that we are indebted to life on Earth, to which owe our allegiance and stewardship. Equally, we owe a debt to our species for its curiosity and inventiveness, for its knowledge and healing, for its organization and synergy, and to all those who have applied these gifts to assuage suffering and empower both individuals and humanity to realize their highest potential.

Why are these things true? Because they are self-evident and self-consistent. 

And from them we can derive principles. Where some see nature as “red in tooth and claw” and build justifications for conquest and rapacity, we can look at the community and creativity, the trust and care, the inventiveness and tolerance which have actually kept us alive —the values that have brought us to the edge of exploring the stars— and say instead “the purpose of power is to protect the weak; the value of leadership is to elevate others.”

Of course, you may not believe it's possible for humans to be the source and genesis of the meaning of life. But can’t we at least set a direction, a path that values life as one, humanity as one, and works to minimize suffering and maximize accomplishment?

It might seem impossible, but we can at least take on the challenge and strive to.  How hard could it be?