The only motives that influence all human actions arise from self-interest. It is clear, ttherefore, that self-interest is the chief influence on human action. The reasoning in the argument is fallacious because the argument ['denies that an observation that a trait is common to all the events in a pattern can contribute to a causal explanation of the pattern', 'undermines its own premise that a particular attribute is present in all instances of a certain pattern or class of events', 'concludes that a characteristic of a pattern or class of events at one time is characteristic of similar patterns or classes of events at all times', 'takes the occurrence of one particular influence on a pattern or class of events as showing that its influence outweighs any other influence on those events']