Scientific tools for assessing positive emotional states in animals are advancing, enabling welfare assessment to go beyond the absence of suffering to evidence of positive experience.
The scientific capacity to assess positive welfare states — not merely the absence of suffering — has advanced substantially in the past decade. Judgement bias tests, which measure whether animals interpret ambiguous stimuli as positive or negative, provide a validated window into emotional valence that is not available through observation of overt behaviour alone. Play behaviour, which represents a positive motivational state requiring sufficient resources and safety to express, is a robust positive welfare indicator. Facial expression coding approaches now extend to positive as well as negative affect in some species. These tools enable welfare assessment to ask whether animals are experiencing pleasure, curiosity, and satisfaction — states that constitute the good life — rather than only whether suffering is absent. Embedding positive welfare assessment into farm, zoo, and research facility standards raises the bar from tolerable to genuinely good.