Yet, the conversation is shifting. The majority of humans are no longer asking if animals matter, but how much . As the science of animal pain becomes undeniable, the gap between welfare and rights narrows. A world that genuinely enforces the "Freedom to Express Normal Behavior" for a pig is a world that looks very different from a factory farm. And a world that looks very different from a factory farm might just be a short step from a world that doesn't eat pigs at all.

Lab-grown meat sidesteps the entire debate. If meat can be grown from a single cell biopsy (without a brain or nervous system), the rights advocate gets abolition (no slaughter), and the welfare advocate gets the end of factory farm suffering. The tension remains, however, regarding the use of fetal bovine serum in production.

Recent research suggests octopuses and crabs feel pain. Rights philosophy struggles here: Do we grant a right to life to a cockroach? Welfare science asks: "What is the least stressful way to kill this pest?" The lines are blurring with advances in neurobiology.