For the full text, follow this link (Local website only): PDF File1.
- Sub-Title: "A cat is alive, a sofa is not: that much we know. But a sofa is also part of life. Information theory tells us why."
- Michael Lachmann is a professor at the Santa Fe Institute in New Mexico. He is interested in the interface between evolution2 and information, and in particular the origins of life.
- Sara Walker is an astrobiologist and theoretical physicist at Arizona State University, where she is deputy director of the Beyond Center for Fundamental Concepts in Science, associate director of the ASU-Santa Fe Institute Center for Biosocial Complex Systems, and assistant professor in the School of Earth and Space Exploration.
- For the full text, see Aeon: Lachmann & Walker - Life ≠ alive
- This is an important paper and deserves more careful consideration than I can give it at the moment. For now, just a few jottings.
- The authors connects connect Life3 with Information4 that has been accumulated by Evolution5, though it’s not clear to me whether this is necessary.
- However, ‘Living’ is something that something that is Life6 does – in particular by metabolising and reproducing. They don’t think that Earth-style biology (or any biology) is necessary for either Life7 or living.
- Early in the paper mules – which troubled Aristotle – are mentioned: while they are sterile, you’d hardly call them dead. I wasn’t clear how the authors’ proposal resolved this conundrum.
- However, they are happy to have explained viruses – which they say are Life8 but not alive, as they don’t metabolise independently.
- I sometimes wondered whether they were just arguing over Semantics9. I think that both Life10 and ‘alive’ are natural kind terms for which there may be a correct – if currently unknown – definition. But while I agree there is no mysterious ‘life-force’, I don’t think defining Life11 as evolved Information12 will do.
- Dead things are – according to the authors – Life13, rather than merely evidence of past Life14.
- They describe a TE15 towards the end of the paper whereby self-replicating 3D printers that mine their raw materials from the environment, suggesting that they are both Life16 - if they have developed via Evolution17 form simpler models – and living.
- They count sofas as part of the web of Life18, as they have evolved from simpler chairs, but not as alive. Personally, I think it’s an abuse of language. Life19 has to be capable of – or have once been – living.
- "Schrodinger (Erwin) - What is Life?" receives a positive mention.
- There’s a mention of Schrodinger’s cat, though I doubted that the conundrum was solved – while it remains as Life20 - according to the authors – it’s still a superposition of alive and dead states.
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