Actually, my answer is based on what philosophy I've picked up from Andy and Jon over the years, and not science-y at all, except inasmuch as science is based on philosophy. Philosophy is at its core about truth and the nature of the world, and the natural sciences (and indeed the scientific method) are a direct outgrowth of that. Your answer falls more into the realm of psychology, which is all about subjective perception of the world, which is okay if you are trying to change your or someone else's subjective perception (what a psychologist does when attempting to work through a neurosis), but is largely useless for drawing any sort of conclusions about the world around us. Look at the number of extant psychological theories: most contradict each other, but all are in use by one psychologist or another, and have been used to good result. The saying Dave posted may well belong to this category of statement, which makes it an aphorism -- something that sounds good, but has no meaning besides that which is assigned to it by the listener. (It can be argued that all language is a form of this, but I'll save that for later -- look up "intersubjectivity" if you're curious.)

Wow, guess I got more out of those dinner table discussions than I thought... but someone please correct me if I'm wrong.