A determination system includes a head electrode that is located on a left head portion of a user when an intention of the user to move a portion on a right side of a body of the user is detected and that is located on a right head portion of the user when an intention of the user to move a portion on a left side of the body of the user is detected； an ear hole electrode that is located in an ear hole of the user； an electroencephalogram signal measurer that obtains a voltage between the head electrode and the ear hole electrode； and a determiner that determines whether or not a change in the voltage includes the intention to move the portion on the right side of the body or the intention to move the portion on the left side of the body.
