This article applies rational choice theory to analysis three reformative periods in 19th century Iran: the reforms of AmirKabir, Naser-ed-Din Shah and Sepahsalar. It analyses the arguments of the advocates and opponents of reforms, as well as the reasons and counterarguments of reformers. Using the method of agreement and the method of concomitant variation, it examines the triangular rational interaction of opponents, reformers, and advocates of reforms. Based on a nominal comparison of the arguments of opponents, the reasons they offer in all three reformative periods include: "endangerment of Shah's household", "homeland security disturbance", "the danger of losing territorial integrity of Iran", "political dependency of the reformer and/or his advocates on foreign countries", "neglecting people's rights", "neglecting the opponents' position and threatening their class benefits", and "personal manner of the reformer and/or his advocates". Based on an ordinal comparison, the most repetitive arguments offered by distinct groups of opponents include: "endangerment of Shah's household", "neglecting the opponents' position and threatening their class benefits", "neglecting traditions by the reformer and/or his advocates", and "personal manner of the reformer and/or his advocates". Analysing the triangular interaction of the reformer, advocates, and opponents of reforms indicates that the reform of Sepahsalar is the only one that demonstrates an interaction among reformer, advocates, and opponents. Further, it is the only period in which the reformer and the advocates react to the most repetitive arguments of opponents.