Though mushin can be realized through kendo as well as through other human activities, there is a slight difference between what the two attempt to realize. Compare, for example, the mushin (in this case the flow-state) required in kendo practice with that required in studying math, science, or a foreign language. Both require perseverance and alertness, but in the former, these attributes are designed to develop the speed necessary to cope with an opponent. The attribute involved in cultivating mushin in kendo can be implemented in studying math, etc., but not vice-versa. That is simply because, as said, in addition to perseverance and alertness, kendo requires speed.