1. A radiation image capturing system comprising: an image capturing apparatus for capturing a radiation image of a subject by irradiating the subject with a radiation emitted from a radiation source; a supply apparatus for supplying image capturing instruction information for capturing a plurality of radiation images of the subject; and a sorting apparatus for sorting the supplied image capturing instruction information into a predetermined processing order; wherein the image capturing apparatus is controlled to capture the radiation images of the subject according to the processing order of the image capturing instruction information which has been sorted by the sorting apparatus; and wherein the sorting apparatus receives the instruction information for capturing the plurality of radiation images as a plurality of instructions in a first sequence and sorts the plurality of instructions into the predetermined processing order, said predetermined processing order being different than the first sequence.