Timescales

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Civilization

Modern human civilization is about six thousand years old – the first real cities arose in Mesopotamia about 4000 BC, give or take a few hundreds of years. Settled civilization (e.g. farming) is maybe six to eight thousand years older than that.

One human generation is generally regarded to be about 20-25 years or so. That means that from you and me, back to the dawn of human civilization is only about 450 generations. If we think in terms of lifespans, the number shrinks even more. From you, back through someone you knew (like a grandparent), back to the first real city-dweller is only about 100 “hops.” Even former US President John Tyler (1790-1862) has two surviving grandchildren; those “generations” are at least 76 years.

Humans and Life

If each breath you take represents one past generation, and you start counting when you wake up, we would arrive at the beginning of recognizably modern humans before lunchtime. Life of any kind on Earth is about 3.5 billion years old. Even using the same lifespan number (which is way too conservative – i.e. mice don’t live for 40-50 years) there are something like 100 million generational hops from you back to the origin of life.

The contrast between the ages of civilization, humanity, and all life amazes me. From 1x to 20x to 350,000x. There may be only about 100 degrees of separation from me to Hammurabi. But the if the entire screen you’re looking at right now represents the age of all life on Earth, our modern human history is about the size of the period at the end of this sentence. <– (that was is it back there).

Lifespans

Humans seem to have an intuitive understanding that fades with scale. Given a jar of marbles, we can pretty easily estimate the number in the tens or hundreds. But one thousand or ten-thousand marbles don’t seem too different. For time-spans, we seldom see forward more than 5 to 10 years, and back maybe 20. Yet we may live 80-plus. We generally don’t even think in timescales of more than a third of our lives!

The constitution of Japan was written within living memory, and has had a profound impact on the shape of that society. A generation in the West has grown up knowing only ubiquitous, always available internet. Whenever a concepts has existed for more than a generation or so, we seem to regard it as fixed - it always was, and always will be. Consider the notion of a strong, independent press, holding government in check. This notion has existed in some form for more than 200 years, but only in the last 75 or so years has the concept of the bulwark of an independent daily newspaper existed, rooting out corruption in local government and holding local politicians to account. Yet most of us live within a context that’s maybe a third as long as that! No wonder we see the ephemeral as “permanent!”

Yet so what? The concepts I hold as dear are all relatively new – what does that matter? It means that changes come and go, and can get institutionalized – and de-institutionalized – in about 1-2 generations time. That is not so long in either the lifetime of a human and certainly not of humanity. What I regard as “the way things have always been” is really just “the way things have been for the last generation and half,” really. Within 400 years – perhaps 5 lifetimes, Rome was a small monarchy, a republic, and then a dictatorship. Germany did that transition and more within a single lifetime.

“Progress” is not always linear. Stability is an intra-generational illusion.