1. A robot apparatus having a behavioral model for outputting a pre-set behavior command or a feeling model for outputting the feeling information, said robot apparatus comprising: detection means for detecting extraneous states; storage means for storing data; write control means for writing pre-set data in said storage means based on said pre-set behavior command or said feeling information; erasure control means for erasing pre-set data stored in said storage means, wherein said erasure control means erases said pre-set data from said storage means based on said pre-set behavior command or said feeling information; and a plurality of legs for walking.