Large numbers and long periods are difficult to understand

First draft

2026-09-15

The evolution has equiped us with nimble abilities to comprehend quantities and time spans - but only relatively small ones. In order to properly think about things like complexity or the evolution itself we must handle vast numbers.

How much is many

Take three different kind of things - say an apple, a banana, and a carrot - and put them on the table in front of you. Closing your eyes you can easily remember in which order they are. You can quite easily imagine them in other orders too, Apple Carrot Banana, BAC, BCA, CAB, and CBA. Three is not very many. Add a Date, an Elderberry, a Fig, and a Guava and you have a lot harder time imaginig all 5040 ways you can mix your fruits.

Or spend an evening with three persons you haven't met before. The next day you have no problem remembering their names and quite a lot of their personal details, and a bit of their life stories. With ten persons it would be a lot harder to remember where Alice lives, what Bob does for living, what hobbies Cathy has, and was that tall guy John or Jonathan. Next night we get about 90 persons more there with you, and you'll be able to remember only few of their names and actually you are not quite sure how many there were exactly. The following day we need a stadium for you and ten thousand stranges, and how hard you try, you'll only get to talk to very small portion of that crowd, remember anything about even smaller portion, and you are likely to guess the number of the stranges off by at least a couple hunderd.

For a reqular person ten thousand is already very many indeed. No wonder that the English word "myriad" comes from Greek word for 10,000 or that Tao Te Ching uses "Ten Thousand Things" to mean all things that exist.

How long is time

• What did you have for lunch yesterday?
• What did you do this day a year ago? How about ten years ago?
• What was your favourite toy when you were five?
• What was it like to be a child when your grandmother was five? How about your great-great-great-grandmother?
• What was a regular day like for your ancestor one thousand years ago? Or ten thousand years ago?
• How did hominids spend their days four million years ago.

Was imagining the last one difficult? Does it feel really, really long time ago? Now multiply it by one hundred? And then by 10,000 - which we know is a large number to think about. Imagine that time span of 4,000,000,000 years, the cuckoo clock cuckooing 35,040,000,000,000 times for full hour. That is how long time life has had to evolve on this planet.