"Heroism is an extreme form of prosociality, a category of behavior that involves benefiting another" (37).

"Here we define heroes as those who incur costs (e.g.) risk of injury or death; or significant sacrifices such as time, money, or other forms of personal loss) to deliver greater-than-expected benefits to others (Baumard & Boyer, 2013). That is, among many actors who engage in behaviors of a given cost, heroes are those who deliver many more benefits to others. Typically these costs are incurred by the hero without certainty and/or negotiated expectation of direct future rewards" (37).

"Prototypical heroes are characterized by physical feats, bravery, and high risks of serious injury or death, such as war heroes or individuals who save others from peril. Folklore heroes such as Superman and Batman are deemed heroic for similar reasons: Their (fictive) willingness and superior ability to incur potentially high costs (e.g. deadly fights with various villains) to save others from danger and threat" (37).

--> displaying/signaling superior physical prowess