Observations and studies of behavior suggest that information learned in one context is often unavailable for use in another situation, even when the other situation would be an ideal place for the stored knowledge. For example, I could spend all day in physics class learning about the properties of a fulcrum. On the way home, thou, my car might get stuck in the snow, and the idea of a fulcrum might not enter my mind at the exact time when knowledge about leverage might do the most good.

Knowledge and information appear to be stored contextually; that is, our brains are highly attuned to context. Information gained in one setting might readily be called upon in that setting again, and the same information might remain dormant outside the context where the information was originally learned. (p. 41-2)

The need to balance fuel and to devise a quick but adequate solution provides a useful way of considering the brain. To balance competing needs, the brain takes all sorts of shortcuts when it processes information, and absolute accuracy is not one of its strengths... Our brains place a premium on 'previous solutions' and recycle those whenever possible, often without awareness of when or how those solutions came into existence.

Traditionally, human thinking has been described with such words as 'rational,' with the assumption that our thinking should follow formal rules of logic. However... our thinking is context-specific and very practical. The primary operating directive for the brain is to find a quick serviceable solution and move on. The less thought required, the better, from the standpoint of time and fuel consumption...

Generally, our brains show a marked bias toward believing (as opposed to disbelieving)... It is much quicker for the brain to have a built-in bias when evaluating new information than be forced to fully consider all the possibilities. (p. 58-60)

Labels are applied to someone [or some thing by our minds] and then inferences are made on the basis of those labels. Although we can acknowledge our own biases, to some extent, to do so is not the first response of our brains. The first response is governed by the needs to save fuel and time and to devise an adequate solution quickly, usually by relying on an 'old' solution.
...
In sum, our brains constantly scan the world. Mostly, we look for information that confirms what we already believe. Then, usually on the basis of past experience, we look for a match between the past and what is going on now. We make comparisons quickly based on the most obvious characteristic of a new situation, typically drawing upon previously used responses or conclusions... For any of us to analyze our thinking or beliefs, we have to be motivated to do so because it takes more energy to ponder our own conclusions. However, if we think we have solved the problem at hand, then we are not motivated to look farther for a solution. (p. 65-6)

Simple takes priority over complex over time. If a simple idea explains a phenomenon, or appears to, then someone will not be motivated to look deeper into a problem...

This tendency to stop at a simple answer, however, can be mitigated in two ways. First, we can accept the possibility that our hypotheses might be incorrect, which provides additional motivation to look for alternative explanations. Second, we can actually check our assumptions by testing them. Each of us employs scientific processes from time to time. We can devise simple experiments to see if our conclusions are valid. In fact, one of the simplest 'experiments' is to seek the opinions of others and see if they agree or disagree with conclusions we have already reached. By doing so, we may discover an aspect of some problem that we had not seen or anticipated. (p. 69)

We do not remember all raw sensory data, if any, partly because there is too much going on at any given time for us to store it all. Thus, we remember events only after our brains have assigned meaning to them. What happens, then, if our brains assign an incorrect meaning? I once had a client tell me that he was at a cemetery as a boy of three, for a funeral. He still maintains a vivid recollection of seeing a ghost. However, three-year-olds are capable of seeing and believing things that you or I would interpret differently. A three-year-old, for example, can believe in Santa Claus, but when we see 'Santa' as adults, we recognize this as an adult in a costume. When children form memories early in life, they store those memories on the basis of their age, and some of those memories persist for life, and the original meaning assigned by a three-year-old brain may not have been updated. (What makes this point more significant is that past memories influence how we interpret new situations.)

Each of us, in effect, may grow more certain of our worldviews, partly because, as we form memories, we subsequently interpret new events through old memories... As we each filter the landscape through preexisting beliefs and memories, we are more likely to see things that conform to preexisting worldviews and less likely to see things anew. Memories not only store experience after we have interpreted that experience, but memories also provide us with a pair of colored lenses through which we see the world. (p. 69-70)

The concept of 'denial' is widespread in our culture. Generally, people use the term to imply that someone is blocking essential information from his or her mind, or ignoring that information... Each of us selectively attends to any situation in light of our personal needs, so what appears like denial to others may only be the way our brains select and choose what is personally relevant at any given moment... There is no doubt that people engage in thinking mechanisms that help them ward off fear or anxiety. We often divert our attention from something that is unpleasant. However, the tendency to attend to some aspects of a situation and ignore others is a well-documented human characteristic that should not always be considered to have a defensive purpose. Our brains are masters at shifting focus, depending on our current needs. We are highly dependent on moment-to-moment changes within the environment, and the brain places more emphasis on immediate outcome than future [unpleasant] possibilities. (p. 71-2)

'Higher' (presumably more sophisticated) stages of cognitive development have been hypothesized to exist for some adults. One such stage has been termed 'post-formal operations.' This style of thinking is unique to humans, but presumably it is only found among some humans. Thus, even individuals with average intelligence may not develop post-formal operational thinking.

Post-formal operational thought describes a thinking style that permits us to recognize that even our most cherished beliefs might be mistaken...

The best thinkers spend more time contemplating their own problem-solving strategies. In turn, when we contemplate our own mental processes, we are more likely to spot problems in logic. Spotting logical errors, in turn, often produces a more thoughtful exploration of alternatives...

We learned earlier that the brain's first response is not to second-guess its own conclusions; rather, its first response is to believe. It would appear, though, that more gifted thinkers recognize the possibility of error and are more likely to look for error. Clearly, some people are more adept at seeing numerous aspects of a problem, while others are stuck with a single perception. Part of the reason for this difference may stem from differences in brain development. One reason for this speculation is that adults often show differences in thinking, contrary to a common myth. (p. 84-5)