1. A control device of a robot arm for controlling a motion of the robot arm, comprising: a first information obtaining section that obtains a plurality of pieces of time-series teaching information at a time when a person operates the robot arm and teaches a motion; a second information obtaining section that obtains (i) reaction time information and (ii) dispersion information at the time of teaching the robot arm; an order determining section that determines an order of the plurality of pieces of teaching information obtained by the first information obtaining section based on the reaction time information and the dispersion information obtained by the second information obtaining section; and a motion creating section that creates motion information as information about the motion of the robot arm based on the plurality of pieces of teaching information and the order, wherein the time-series teaching information includes at least one or more of a position, an orientation, and a speed of the robot arm, the reaction time information is time information from a time when the person receives perceptual information to a time when the person operates the robot arm, the perceptual information being at least one of information about a force applied from the robot arm to a target object for a task by the robot arm, information about a position of the target object for the task by the robot arm, and sound information of a circumference environment, the dispersion information is information about a dispersion level in chronological order between at least one or more pieces of the teaching information in chronological order and the perceptual information in chronological order, and the motion of the robot arm is controlled based on the motion information created by the motion creating section.