Is artificial life actually alive?

Something in this world was born, ate, moved, carried a rock, had offspring that were slightly different from it, and died. If you watched it without being told what you were looking at, you would reach for the word alive. The interesting part is not whether that word is allowed. It is which of the things you mean by it are actually true here.

The textbook answer, and why it does not settle it

Biology textbooks usually offer a checklist: metabolism, growth, reproduction, response to stimuli, heredity with variation, evolution. It is a useful list and nobody who works on the definition of life thinks it is a definition. Fire metabolises and grows. Crystals reproduce their own structure. A mule does not reproduce at all.

Run the checklist here anyway, because the answers are unusually clean:

• Metabolism. Yes, and it is audited. Every organism spends energy to exist and dies when it runs out. The books have to balance to a tolerance or the universe halts rather than continue - the accounting is published.
• Reproduction with heredity and variation. Yes. Offspring inherit a genome that mutates. Family lines are tracked from the first organisms.
• Response to stimuli. Yes. Each organism reads 53 channels of its own situation and acts on them through a neural network you can open and inspect.
• Evolution. Yes, and measured: one family line's inherited movement policy took over an entire world in about fifty thousand ticks, and that was read off the universe's own frozen test battery, not inferred from behaviour.

That is a better score than most things people argue about. It still does not make the answer yes, and the reason why is more interesting than the checklist.

The real objection is about stuff, not behaviour

When people say a simulation is not alive, they rarely mean it fails the checklist. They mean something closer to: it is not made of anything. A bacterium is a physical object with chemistry happening inside it. An organism here is a pattern in memory, and the pattern would be identical if the computer were made of valves, or of people passing notes, or of water running through pipes.

That objection is serious and it is not obviously right. The same argument applies to you at one remove: the atoms in your body are replaced over years, and what persists is a pattern, not the stuff. The difference is a matter of degree - how much the pattern depends on the particular physics underneath it - and nobody has a principled place to draw the line.

What this project will and will not say

This world is deliberately built so the question can be asked carefully rather than answered loudly. There is no reward for surviving, no score, no goal, and nothing in the code that describes what an organism is for. Nothing here is trying to be lifelike. When an organism does something that looks purposeful, there is no line of the program that wanted it to.

So the honest position is this. Every behavioural property on the checklist is really here and can be measured by anyone. Whether that makes it alive is a question about what the word means, not about what this world does, and no amount of further observation will settle it - which is a fact about the word, and worth knowing before the argument starts.

See it and decide

The usual way this question gets argued is with nothing on the table. Here there is something: open the live world, pick a creature, and open its brain. Then ask yourself which part of your answer was about the creature and which part was about the word.

What "life" has been taken to mean · Could a simulation be conscious? · Why nothing here wants anything