and heart rate [27], and sometimes blushing or stammering [28]. In contrast to the Social

and heart rate [27], and sometimes blushing or stammering [28]. In contrast to the Social Heuristics Hypothesis, our model also predicts that decisions related to cooperation are more likely to be intuitive than other decisions that are similarly usually worthwhile, and that intuitive cooperators are trusted more than reflective cooperators. To our knowledge, neither of these predictions has been tested yet. People dislike considering trade-offs related to “sacred values” [29]. Sacred values are values such as love, liberty, honor, justice, or life, that people treat “as possessing transcendental significance that precludes comparisons, trade-offs, or indeed any mingling with secular values” [29]. While there is variation in what societies consider sacred, virtually all societies have a concept of sacredness [29]. Sacred values are so strongly imbued in us that we do not find them puzzling prima fascia, yet their existence and origin remains poorly understood. What makes us treat some values as sacred and what differentiates these values from secular values like free time or money that we more readily trade off? Our model provides one possible explanation. People who calculate costs of trading off against sacred values are less trustworthy when it comes to safeguarding these values than people who consider them sacred and would never calculate the costs of trading off against them. Responding with disgust to these “taboo trade-offs” may be one way to prevent us from interacting with people who make such trade offs and hence are less trustworthy, and may also be a way to signal to others that we ourselves would not consider, and therefore make, such trade-offs. Consistent with CWOL, it is taboo to consider the trade-off even if one ultimately makes the right choice, and the longer the trade-off is considered for, the harsher the judgement by observers [29]. As with intuitive cooperation, if people who refuse to consider taboo trade-offs are seen as more trustworthy, this may lead people to evolve or learn to abide by these taboos. If CWOL indeed underlies iim HOUSE_OVERSIGHT_026531