A system for endoscopic surgery having a function of controlling, through voice recognition, a connected peripheral device, comprising: a storage unit that is configured to store a command for controlling the peripheral device and whether or not the command is valid or invalid in an associated manner for each operator and each procedure of an endoscopic surgery; a specification unit that is configured to receive specification of the operator and the procedure; a conversion unit that is configured to recognize an input voice, and to convert the voice into a character string; a determination unit that is configured to refer to the storage unit, and to determine whether or not the character string obtained by the conversion unit is identical to a command that has been set to be valid for the operator and the procedure specified by the specification unit; a transmission unit that is configured to halt a transmission process to a peripheral device that corresponds to a command that has been determined to be invalid by the determination unit; and a scene specification unit that is configured to receive specification of a scene representing a step of the endoscopic surgery, wherein: the storage unit is configured to store, for each of the operators and the procedures which are used in the endoscopic surgery, whether each of the commands is valid or invalid for each of the scenes; and when a scene has been received in the scene specification unit, the determination unit is configured to determine whether or not the character string is identical to a command that has been set to be valid in the storage unit for the received scene for the operator and the procedure received in the specification unit. a storage unit that is configured to store a command for controlling the peripheral device and whether or not the command is valid or invalid in an associated manner for each operator and each procedure of an endoscopic surgery; a specification unit that is configured to receive specification of the operator and the procedure; a conversion unit that is configured to recognize an input voice, and to convert the voice into a character string; a determination unit that is configured to refer to the storage unit, and to determine whether or not the character string obtained by the conversion unit is identical to a command that has been set to be valid for the operator and the procedure specified by the specification unit; a transmission unit that is configured to halt a transmission process to a peripheral device that corresponds to a command that has been determined to be invalid by the determination unit; and a scene specification unit that is configured to receive specification of a scene representing a step of the endoscopic surgery, wherein: the storage unit is configured to store, for each of the operators and the procedures which are used in the endoscopic surgery, whether each of the commands is valid or invalid for each of the scenes; and when a scene has been received in the scene specification unit, the determination unit is configured to determine whether or not the character string is identical to a command that has been set to be valid in the storage unit for the received scene for the operator and the procedure received in the specification unit. the storage unit is configured to store, for each of the operators and the procedures which are used in the endoscopic surgery, whether each of the commands is valid or invalid for each of the scenes; and when a scene has been received in the scene specification unit, the determination unit is configured to determine whether or not the character string is identical to a command that has been set to be valid in the storage unit for the received scene for the operator and the procedure received in the specification unit.