If we believe in our potential to be evil, we must consider from where this tendency arises—is it an innate characteristic of human nature, or perhaps a nurtured trait of circumstance? Tetsuo is in nature an impatient and frustrated child, but still a reasonably moral individual. Once he gains inconceivable power, his frustrations turn into rage and we see the impatient child become the murderous and maniacal monster—a disturbing transition.