This paper examines historic appraisals of string theory to develop a less abstract understanding of the string theory controversy and assessment in non-empirical physics. This historical approach reveals several points of conflict in the controversy, each centring on a constraint. By proceeding stepwise through these constraints, I reveal the role that constraints played in determining divergent assessments of string theory. Rather than disagreement between two competing methods, a level of agreement is found amongst those critical and supportive of string theory as to the commitment to the relevant constraints, but disagreement as to the sufficiency of consistency, the path to background independence and a non-perturbative formulation, and how to interpret the significance of applications. Furthermore, the string theory community itself is shown to be divided in its commitment to the necessity of uniqueness and the legitimacy of anthropic reasoning. These varied assessments, guided by considerations of constraints, have informed divergent claims as to the past and future fertility of string theory. These are claims as to the value of string theory in guiding research in quantum gravity: claims as to whether string theory has and will be valuable as a means rather than an end.

本文考察了弦理论的历史评价，以对弦理论争议和非经验物理学中的评价有一个不那么抽象的理解。这种历史方法揭示了争议中的几个冲突点，每一个都集中在一个约束上。通过逐步处理这些约束，我揭示了约束在确定弦理论的不同评估中所起的作用。与其在两种相互竞争的方法之间存在分歧，不如在那些批评和支持弦理论的人之间发现了在对相关约束的承诺方面存在一定程度的一致，但在一致性的充分性、背景独立性的路径和非微扰方面存在分歧。公式，以及如何解释应用程序的重要性。此外，弦理论社区本身在其对唯一性的必要性和人择推理的合法性的承诺方面表现出分歧。这些不同的评估，以对约束的考虑为指导，对弦理论的过去和未来的丰产性提出了不同的主张。这些是关于弦理论在指导量子引力研究中的价值的主张：关于弦理论是否已经并将作为一种手段而不是目的有价值的主张。