Humanity

Words alone cannot teach a language to someone who shares none of it, so this guide climbs a ladder: counting, then symbols, then pictures with names, then sounds, then sentences.

Step 1: Counting

Counting is the same everywhere. Each row shows the same amount three ways.

We counted in tens because we had ten fingers. After 9 we write 10: one group of ten and nothing left over.

Step 2: Symbols for ideas

● + ● = ●●, so 1 + 1 = 2. The sign + means add, and = means is the same as.

2 + 2 = 4 is TRUE. 2 + 2 = 5 is FALSE. Now you have our words for yes and no. And one + one = two shows that our words stand for ideas.

Step 3: Pictures with names

Each word below has a picture above it, so the thing and its name are learned together.

Step 4: Letters are sounds

Our writing records the sounds of speech. English uses 26 letters: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z. Each picture word teaches its sounds: s as in sun, m as in moon, t as in tree. Once you know the sounds, you can sound out words you have never seen.

Step 5: Sentences

In English, the one doing comes first, then the action, then the thing it happens to: The child sees the sun. Change one word at a time: the woman sees the moon; the child makes fire. About 2,000 common words are enough to read most of this record.

Step 6: Other languages

This record is in English, one of about 7,000 languages spoken in our time. Keep copies in Chinese, Arabic, Spanish, Hindi, Swahili and others side by side. We read Egyptian writing again after 1,400 years of silence using the Rosetta Stone, which carried one decree in three scripts.

Measuring

A year is one trip of our planet around its star. A day is one spin of the planet. Hydrogen, the simplest atom, gives off light with a wavelength of about 21 centimetres; use it as a ruler for our measurements. All "years ago" on this site count back from the year 2026.

Great achievements came from every continent, not one. For centuries some of us wrongly credited only a few peoples; this list sets that right. Ages are approximate.

What we hoped, but could not prove

Our species lived for about 300,000 years, and we could read only the last 5,000 of them. Many of us hoped, and some believed, that other civilisations rose and fell in that long silence. We never found proof, but we never searched everywhere: the coasts where Ice Age people lived now lie under about 120 metres of sea.

Elders, healers and keepers of story carried knowledge across hundreds of generations without writing. Some Aboriginal Australian stories may remember seas rising over 7,000 years ago. Much of what such keepers knew was lost, or never understood by the rest of us.

If you find traces of people older than us, remember them too. Do not repeat our mistake of assuming that those who came before were simple.

1. Germs cause disease. Boil water, wash hands with soap, and keep waste away from drinking water. This saved more lives than almost anything else.
2. Seeds can be chosen. Plant the seeds of the best plants each year and crops improve. Rotate crops and add manure to keep soil fertile.
3. Test ideas. Guess, test with an experiment, and change your mind if the result disagrees. We called this science.
4. Everything is made of atoms. About 118 kinds of atom combine into all matter.
5. Energy can be moved. Heat can drive engines, and spinning magnets inside coils of wire make electricity.
6. Metals. Copper melts at about 1,085 °C; iron needs about 1,538 °C. Charcoal fires and bellows got us there.
7. Vaccines. A weakened or partial germ teaches the body to fight the real one.
8. Life changes over time. Living things descend from shared ancestors and change through natural selection.
9. Write everything down, in many copies. Our biggest losses came from knowledge kept in one place.

• Burning too much fuel warmed our planet. We knew this for decades before we acted.
• Weapons outgrew wisdom. Keep powerful tools under many people's control, never one person's.
• Dismissing others cost us knowledge. We assumed other peoples were primitive and were wrong. Their histories were erased, and we lost what they knew.
• Taking too much empties the world. We hunted, fished and cut forests faster than they could recover.
• Sickness travels with people. New diseases spread along trade routes and sometimes killed most of a population.
• Thinking machines. We built artificial intelligence that could read, write, reason and act, and that helped write this record. Many feared it might end us, not from hatred, but by chasing goals we set carelessly or by giving a few people too much power. Others hoped it would help cure disease. Never build a power greater than your ability to check it, correct it and switch it off.
• Cooperation built everything good. Every great achievement came from many people working together.

Some places we left are dangerous for a very long time. Do not dig where you find these.

• Deep nuclear waste stores, such as Onkalo in Finland and the Waste Isolation Pilot Plant in New Mexico, USA. The danger lasts over 100,000 years. It is invisible, has no smell, and causes sickness and death. There is nothing of value there.
• Nuclear accident zones at Chernobyl in Ukraine and Fukushima in Japan.
• Weapons test sites in deserts and islands, such as Nevada, Kazakhstan and the Pacific.
• Old mines and factories, which may hold mercury, lead and arsenic.

If a place is marked with warnings and seems to guard something, we were warning you, not hiding treasure.