The political atmosphere on US college campuses is overwhelmingly left-leaning and liberal, with the vast majority of faculty self-identifying as socially progressive. Considerable research on cognitive biases has demonstrated the pervasive role of people’s attitudes, which act as filters during thinking and reasoning – particularly about politically-valenced topics. The prevalence of faculty from one side of the political spectrum coupled with the omnipresence of cognitive biases means that college campuses and the research done by their faculty runs the risk of favoring one side during what should, scientifically-speaking, be a process of fair and open inquiry. We discuss these phenomena and document numerous examples in which lack of genuine viewpoint diversity has spelled trouble for sound science. We advocate a more ideologically-diverse scientific workforce to better enable true diversity of thinking on key issues of our time.

There are large between-country differences in measures of economic and noneconomic well-being. Many researchers view increasing the stock of human capital as the key to raising economic development, promoting democratization, and improving health, and hence improving overall societal well-being. The single most studied aspect of human capital concerns cognitive competence. Differences in population cognitive competence might explain these societal differences. Evidence suggests that education builds cognitive competence, and education and cognitive competence promote better social outcomes, in terms of both economic and noneconomic factors. However, measuring population cognitive competence for countries requires representative samples, culture-fair tests, equivalency in the relationship between test measures and other cognitive attributes, and comparability in testing situations. In most cases, none of this has been achieved.

My most important scientific contribution concerns the development of “source misattributions.” That's a fancy term to describe an event that is familiar, but not because we actually experienced it. Instead, it's familiar to us because in the past we either imagined it, or read about it, or saw something related to it on television, or overheard a conversation about it. These prior mental activities reside in memory but sometimes without their source: is this event familiar because I truly experienced it, or is the source of its familiarity having imagined it or heard someone talking about it? Although we all have a propensity for misattributing the source of why something is familiar, very young children are most vulnerable. It turns out that a lot of really important phenomena are related to it, including court cases involving child witnesses.

You may find the way I became interested in source misattributions interesting. In graduate school I studied children's memory. By the time I got my PhD I thought I knew a lot about how children remember. But I was jolted into reality one day when a judge from upstate New York called me at my office at Cornell. He had a case in his courtroom involving a child's recollection that puzzled him. He said someone gave him my name as an expert on children's memory. The gist of the case was as follows: a woman disappeared when her son was twenty-two months old. After several months had passed, and the mother did not return home, her husband took their son to his missing wife's sister and asked her to care for the child. The aunt and father had not had a good relationship, and they were known to have argued vehemently about his mistreatment of her sister. The aunt agreed to care for her nephew until her sister resurfaced. The father moved to Florida, and his contact with his son and sister-in-law was limited. He remarried eventually.

At the time of the judge's phone call, the boy had been living with his aunt for four years. The house in which the boy lived with his parents had been sold and resold, and the newest owners were adding an extension when the excavator discovered the skeletal remains of the missing mother. The coroner's report indicated she had been killed by blunt force trauma to her head by a rounded object.

In the past decade, a new approach to understanding development has been put forward that describes a specific form of interaction between biology and environment, called the “bioecological model” (Ceci, 1996; Bronfenbrenner & Ceci, 1993, 1994). The goal of this chapter is to describe how a bioecological approach informs the study of intellectual development. In doing this, we shall focus on the evidence for the tenet of bioecological theory that is most relevant to intellectual functioning, namely, the knowledge-dependent nature of information processing. Following a description of the evidence for this tenet, we will segue into a discussion of the role of the transferability of knowledge in intellectual competence.

The bioecological approach to development posits a close interplay between knowledge and processing efficiency. What this means in the realm of intellectual competence is that, except for the most basic and dedicated processes (e.g., feature detection), processing efficiency is a function of interaction between genetic potentials for processing and the richness of the knowledge base on which the processes operate.

In this chapter, we tackle a problem that has been at the heart of the debate over the relative influence of genes and environments in producing cognitive competencies. Our goal is to attempt to reconcile the disparate claims of behavior genetics researchers who stress the prepotency of genes in producing intellectual competence (for example, Bouchard, Lykken, Tellegan, and McGue, 1998) with those whom Scarr (1997) refers to as “socialization theorists” because of their stance on the crucial role of the social and material environment in shaping developmental outcomes.

Our means of making this reconciliation is to describe recent efforts by diverse scholars to explain cognitive growth in terms of theories, models, and metaphors that are inherently multiplicative, more so than prior ones. We do not intend to delve into a comparative analysis of the strengths and weaknesses of each model or metaphor, as that is not our goal, but instead we want to make the point that various researchers, coming from very different orientations, have found the need to postulate similar types of multiplier effects to account for cognitive growth across a wide range of attainments (reading, intelligence, mathematics, motoric).

In the treatment that follows we use the terms “proclivities,” “penchants,” and “abilities” interchangeably, to refer to basic, underlying “resource pools” that are undoubtedly biologically based. Thus, we speak of a newborn's penchant, ability, or proclivity to stare, attend, remember, and process the perceptual world.

In her 1958 Presidential Address to APA, Anne Anastasi urged psychologists to move beyond the question of studying “how much” variance was accounted for by genetics and environment and instead to address the question of “how” genotypes were translated into phenotypes. Despite the passage of nearly 40 years, Anastasi's challenge has not been taken up. Today, we know much more than we once did about the role of genetics in intelligence, the distribution of alleles at neurologically relevant sites, and the molecular chemistry of brain functioning, but we still know as little as ever about the mechanisms through which genetics get translated into phenotypic intellectual expression.

In this chapter, we endeavor to say something about the process that translates genes into phenotypes and, in so doing, say something about the environmentally loaded nature of heritability and the genetically loaded nature of the environment. While acknowledging the important role that genetics plays in intellectual development, we shall nevertheless take issue with the traditional “percent of variance accounted for” model of behavior genetics. In its place, we will suggest that traditional heritability measures do not inform us about the manner in which genes exert their influence, nor even about the organism's genetic potential. Rather, they tell us what proportion of individual differences in already actualized genetic potential has been brought to fruition by the prevailing environment. Left unknown, and unknowable from the traditional model, is (1) the amount of the organism's unactualized genetic potential, and (2) the absolute level of intellectual competence around which individual variation occurs.

In 1983 Lenell Geter was given a life sentence for a series of armed robberies that he did not commit. After serving eighteen months in prison, he was released when new evidence revealed that another man committed the crimes. An investigation into the case showed that the prosecution's key witness had made a tragic error. The police had shown the witness a photo lineup shortly after the crime occurred. At that time the witness reported that the assailant was not present in the lineup. Several months later the same witness was shown another lineup. It contained five photographs, four new photographs, and one photograph that had been present in the first lineup. The witness selected the “old” or “familiar” photograph, and the person in the photograph was Lenell Geter. Apparently the witness did not remember having seen Geter's photograph in the first lineup, and as a result she incorrectly associated its familiarity with the crime, and made a false identification (Buckhout, 1984). In a similar case, a ticket agent in a railroad station was the victim of an armed robbery (Houts, 1963; Loftus, 1976; Read, Tollestrup, Hammersley, McFadzen, & Christensen, 1990). From a police lineup the ticket agent identified a sailor who had proof that he could not have been at the station at the time of the robbery. When questioned as to why he misidentified the sailor, the ticket agent claimed the sailor looked familiar to him. An investigation discovered that the sailor lived near the train station, and had purchased tickets from the agent at three different times prior to the robbery.