This paper examines the discussions carried out at the Chosŏn court about the determination of the intercalary month and the printing of the calendar of Year 1735. In doing so, the paper will show the significance that the calendar and the calendrical method had for the king, the government and for the literati scholars in Chosŏn society. It will show various different attitudes and different levels of understanding that the king and his literati ministers had about the specialized knowledge and problems of calendrical method and its specialists of “middle people” class. As a kind of “scientific debate”, the Chosŏn court’s discussion will provide an example illustrating the way in which non-scientific factors and interests entered and influenced the discussion and the decision about a problem of a scientific nature.