Modern animal welfare science increasingly focuses on positive welfare states — pleasure, play, and positive engagement — not just the absence of pain and distress.
The historical focus of animal welfare on preventing suffering — the Five Freedoms framework — represented essential progress but an incomplete welfare vision. An animal that is not in pain, is not hungry, and is not diseased may still be living a life of deprivation if it cannot express species-appropriate behaviors, form social bonds, or engage in positive experiences like play and exploration. The shift toward positive welfare — asking not just "is this animal suffering?" but "is this animal thriving?" — represents a more complete understanding of what animals need. Positive welfare science has practical implications: enrichment programs designed to enable play and exploration, social housing that allows affiliative behavior, and assessment tools like cognitive bias testing that reveal subjective experience beyond observable pain. The goal of animal care should be lives worth living, not merely lives not worth ending.