Final answer:
A humanist would explain aggression as a behavior stemming from frustration when an individual is unable to meet their goals, which is supported by the frustration-aggression theory.
Step-by-step explanation:
A humanist would likely explain aggression as a result of frustration arising from the inability to meet goals. This perspective aligns with the frustration-aggression theory proposed by Dollard, Doob, Miller, Mowrer, and Sears in 1939. According to this theory, when humans are prevented from achieving an important goal, they become frustrated and this frustration can lead to aggressive behaviors. Humanists believe in the importance of individual experience and the innate potential for personal growth. Aggression, then, is not seen as inherently rooted in human nature but is understood as a response to external conditions that thwart personal objectives. From a humanist standpoint, aggression is a behavior that can be addressed by changing the social conditions that elicit frustration.