Should government fund safe human enhancements for the hereditary contribution to good looks or athletic prowess or IQ? Is there reason to restrict genetic interventions that would create chickens without the nesting instincts that agitate normal chickens confined to life in a battery cage? Or cows with stunted emotions that would feel less fear as they were led off to slaughter? Or pigs with no legs  better suited to a sedentary existence as bacon-to-be? Some philosophers argue that political decisions about such practices  to be legitimate  must be made without reference to reasons that arise from within controversial worldviews