Are We Assuming Life Must Be Like Us?
Fine-tuning arguments often ask whether different physical conditions would permit life like the life we know. But perhaps radically different forms of life or complex organization could exist under conditions very different from ours.
Why This Matters
If fine-tuning calculations quietly assume carbon-based terrestrial life at every step, they may define the life-permitting range too narrowly.
Response
This is a legitimate caution. We do not know every form that life or complex information-bearing systems could possibly take.
For that reason, it is safer to focus first on requirements that can be described physically: stable structures, usable energy sources, sufficiently complex chemistry or analogous information-bearing systems, and environments that persist long enough for complexity to develop.
Some evidence concerns carbon specifically and should be identified as such rather than presented as proof that no other imaginable basis for life could exist.
Question That Remains
How different could a genuinely complex, self-reproducing, information-bearing form of life be, and which physical requirements would remain necessary regardless of its chemistry?