DISCUSSIONS ABOUT CHARACTERISTICS OF HUMAN NATURE GENERALLY CAN BE PLACED BETWEEN THE POLES OF NATURE AND NURTURE. THE NATURE SIDE VIEWS THE HUMAN ORGANISM AS RIGIDLY PROGRAMMED BY INBORN PASSIONS AND INSTINCTS THAT ALLOW THE INDIVIDUAL LITTLE ROOM FOR THE WILLFUL CONTROL OF BEHAVIOR. THE BEHAVIORIST CONCEPTION FAVORS THE NURTURE SIDE; HEREIN HUMAN NATURE IS A BLANK SLATE AND THE INDIVIDUAL IS THE SUM TOTAL OF LEARNING EXPERIENCES. ALTHOUGH BOTH CONCEPTIONS OF HUMAN NATURE ARE UNSATISFACTORY, THE VEHEMENCE OF EACH ARGUMENT SERVES TO DRAW ATTENTION TO IMPORTANT DETAILS THAT MIGHT OTHERWISE GO UNNOTICED. ANOTHER THEORY COMBINES NATURE AND NURTURE CONCEPTIONS INTO A FORMULA WHEREBY BEHAVIOR IS A FUNCTION OF THE INTERACTION BETWEEN A SITUATION AND AN ORGANISM. ACCORDING TO THE MIDDLE-GROUND THEORY OF HUMAN NATURE, DEVELOPMENTAL PSYCHOLOGY, THE ORGANISM SIDE OF HUMAN NATURE IS COMPRISED OF NEED POTENTIALS AND DEVELOPMENT-REALIZING STEPS ESSENTIAL TO HEALTH. IN THIS THEORY, THE OPPORTUNITY TO FULFILL NEEDS AND REALIZE POTENTIALS IS A FUNCTION OF THE ENVIRONMENT. TERRORIST BEHAVIOR THEN, OCCURS IN THE FACE OF A HIGH SUBJECTIVE PROBABILITY THAT INDIVIDUALS WILL LOSE THEIR IDENTITY AND OPPORTUNITIES TO DEVELOP THEIR INBORN POTENTIALS. TERRORISTS ARE SPURRED INTO ACTION BY WHAT THEY SEE AS AN ENVIRONMENT INHOSPITABLE TO THE REALIZATION OF THEIR HUMAN NATURE. IN THE CONCEPTION OF DEVELOPMENTAL HUMAN NATURE AS A HIERARCHY OF NEEDS, AN ORGANISM IS SEEN AS A MOTIVATED ENTITY, WITH NEEDS OF IMPORTANCE AS INTRINSIC OR SELF-CONSUMMATORY, INSTRUMENTAL, AND ACQUIRED. TERRORISTS HAVE ACQUIRED A HIGH NEED FOR ACHIEVEMENT, NOT FOR SECURITY BUT FOR POWER. CHARACTERISTICS OF 'COLD HARD' KILLERS AND 'WARM HARD' KILLERS AND OF IDEALISTS ARE EXAMINED. THE RELATION BETWEEN DISRUPTION OF THE FAMILY UNIT AND TERRORISM IS NOTED. FOOTNOTES ARE INCLUDED. (DEP)