[tablespoon]

> Agreed. Skimming Humbird's analysis, he mentions concentrations of catabolites as a significant limit on cell density, and points out that their removal is usually the job of the kidneys. To me that immediately raised the question of how to design an artificial kidney-like structure that can also live in solution. Similarly, the cleanroom conditions are very difficult to sustain, but what if we could engineer a replacement for the immune system to police the reactors?

But then you're talking about re-engineering complex animal life, which is nowhere close to happening any time soon. Plus once you add those systems back in, you may loose most of the energy savings that make "lab grown meat" look attractive. This comment when into more detail and did some back of the envelope calculations: https://news.ycombinator.com/item?id=28623349.

> Speaking as someone who eats meat regularly, it's mostly a matter of conditioning. I don't think I would have independently invented the idea of killing and consuming an animal if other's hadn't taught it to me.

To be fair, you're a human: you had to learn all your survival skills. You wouldn't have independently invented the idea of eating plants either, let alone picking the ones that would give you a nutritionally complete diet without poisoning you.