How important is the fact that the layperson finds the trait a useful construct?

Question Two: Some psychologists have suggested that while individuals tend to use traits to describe themselves and others, this merely tells us something about the cognitive functioning of individuals and about their interpersonal perceptions– it does not tell us that traits represent the best tools for the scientific analysis of personality. How important is the fact that the layperson finds the trait a useful construct? If we accept the importance of the layperson’s use of this construct for theory development, does this also commit us to accepting the specific trait names and categorizations used by the layperson (e.g., honest, aggressive, sympathetic)?
Suggested Topic Heading: Trait Constructs
Question Three: Big five terms are great for describing differences between people. But are they also good for explaining people’s behavior? Is it reasonable to say that “Liz smiled and greeted people happily because she is an extravert”? Or is that similar to saying “It is sunny and warm in San Diego this week because San Diego has nice weather”? In other words, is this sort of “explanation” one that just takes you around in circles?
Suggested Topic Heading: The Five-Factor Model
Question Four: The text discusses research on brain systems involved in higher-level psychological functions, such as self-concept. How much do we learn about such psychological functions by studying the brain? In other words, since we know that some systems in the brain have to be involved in any psychological function, does an analysis of underlying neuroanatomy answer the most pressing questions about personality? Or does it leave unanswered critical questions about the ways in which these psychological capacities develop and function in the social world? In short: Can there be a neuroscience of personality?
Suggested Topic Heading: The Brain and Psychological Functions