International carbon allocation confronts the conflict between efficiency and equality. Previous research based on the intergroup bias perspective has attributed carbon allocation preference to the defence of ingroup interests (i.e., national interests) while overlooking the critical role of trade-offs between competing moral values. Integrating the contingency theory of justice and moral philosophical theories of utilitarianism and egalitarianism, we proposed that the moral-values trade-off between utilitarianism and egalitarianism determines carbon allocation preference through justice reasoning. Analysis of large-scale survey datasets (Study 1) revealed that aggregated national endorsement of utilitarianism over egalitarianism predicted greater efficiency preference in total and per capita carbon emission levels. Study 2 demonstrated that experimentally manipulating endorsement of utilitarianism versus egalitarianism boosted efficiency (vs. equality) preference in carbon allocation, and justice reasoning characterized by enhanced efficiency-focused justice and diminished equality-focused justice accounted for these effects. Using a ‘manipulation-of-mediator’ design, Study 3 further confirmed the causal link in the mediation model. By highlighting the significance of moral trade-offs in shaping carbon allocation preference, this research not only provides a novel moral perspective in understanding debates on international carbon allocation but also has important implications for fostering international carbon abatement cooperation.

中文翻译：

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效率还是平等？功利主义与平均主义的权衡决定碳分配偏好

国际碳分配面临效率与公平的冲突。以往基于群体间偏见视角的研究将碳分配偏好归因于对群体内利益（即国家利益）的捍卫，而忽视了相互竞争的道德价值观之间权衡的关键作用。结合正义权变理论以及功利主义和平均主义的道德哲学理论，我们提出功利主义和平均主义之间的道德价值权衡通过正义推理决定碳分配偏好。对大规模调查数据集的分析（研究 1）表明，国家对功利主义相对于平等主义的总体认可预示着在总碳排放水平和人均碳排放水平上存在更大的效率偏好。研究2表明，通过实验操纵对功利主义与平均主义的认可提高了碳分配中的效率（与平等）偏好，而以增强以效率为中心的正义和削弱以平等为中心的正义为特征的正义推理解释了这些影响。研究 3 采用“中介操纵”设计，进一步证实了中介模型中的因果关系。通过强调道德权衡在塑造碳分配偏好中的重要性，这项研究不仅为理解国际碳分配争论提供了新颖的道德视角，而且对促进国际碳减排合作具有重要意义。