Isn't it just the circle of life?
Short answer: A factory farm runs in a straight line: bred by machine, fed, killed young. The phrase borrows nature's poetry to excuse an industry.
A 'circle of life' that ends most of the way early, for profit, is just a short life and an early death.
Natural lifespan vs typical slaughter age, dairy cattle
The objection
“Life eats life, it always has. The animal lived, it died, something else lives on it. That’s the circle of life, and farming is just our part in it.”
The answer
It’s a beautiful phrase, which is exactly why it’s reached for. Hold it up against what actually happens on a modern farm and the circle isn’t there.
A circle is a cycle: birth, life, death, return, renewal, with no beginning imposed from outside. Industrial animal agriculture is a straight line, and humans draw every point on it. The animal is brought into existence on purpose, usually by artificial insemination. Its mother is impregnated on a schedule. Its diet, its lifespan and its death are all set by a production plan. The overwhelming majority of farmed animals are reared in intensive systems, not roaming an ecosystem. No wheel turns on its own here; this is a conveyor belt, and we built it.
Notice too where the “circle” stops. The phrase invites you to picture a noble exchange, yet a dairy cow whose natural span is around twenty years is killed at five or six when her yield drops. A “circle of life” that ends two-thirds early, for profit, is a euphemism for a short life and an early death.
Even taken at face value, the argument proves too much. If “life eats life” justified anything, it would justify everything, and there’d be no wrong way to treat an animal at all. The instant you agree some treatment is cruel, you’ve conceded that “circle of life” doesn’t settle the question. The manner, the necessity and the suffering still have to be weighed.
Nature recycles. Slaughterhouses don’t, and the poetry of the first shouldn’t launder the reality of the second.