Duarte et al. are to be commended for addressing the important topic of a pervasive liberal ideological bias that potentially undermines the scientific validity of some social-psychological research. Their critique, however, does go not far enough. The bias they identify is far more pervasive than the authors realize. In fact, in the course of their own argument the authors rely upon a particularly egregious example of the very bias they critique.

In addressing the under-representation of conservatives in social psychology, Duarte et al. ask, “[M]ight liberals simply find a career in social psychology (or the academy more broadly) more appealing?” (sect. 5.3, para. 1). Their answer is as follows:

What they fail to realize is that the five-factor model of personality, and in particular the trait of openness to experience, embodies liberal ideological biases rather blatantly.

In the revised personality index of the five-factor model (the Revised NEO Personality Inventory [NEO-PI-R]), the trait of openness to experience is divided into 6 different “facets” (Costa & McCrae Reference Costa and McCrae1992). One of these facets (no. 6) is termed “Values,” and is judged by eight statements. I list here only four (the numbering is mine), although all of the statements listed under Values are equally problematic. Depending upon whether one agrees or disagrees with each of these statements, her scores on Values and on openness to experience go up or down. I have indicated whether the response of “agree” for each statement causes one's score to go up or down:

1. 1. I believe that we should look to our religious authorities for decisions on moral issues. (Agree: Openness score goes down)

2. 2. I believe that the different ideas of right and wrong that people in other societies have may be right for them. (Agree: Openness score goes up)

3. 3. I believe that laws and policies should change to reflect the needs of a changing world. (Agree: Openness score goes up)

4. 4. I believe the new morality of permissiveness is no morality at all. (Agree: Openness score goes down)

Consider how, in the words of Duarte et al. (sect. 3.1), “liberal values and assumptions [are] embedded into theory and method” (in this case, the theory and method of the five-factor model). In considering these statements, I am referring both to the statements themselves and to how they affect one's Values score.

Statement 1 reflects a liberal ideological bias against religion. Is reliance upon scientific authorities, for example, “close-minded”? Granted, the question concerns moral decisions (so let us assume that science cannot resolve questions of right and wrong). Why, then, is reliance upon religious authorities as opposed, for example, to philosophical or ethical authorities, or simply, moral “experts,” singled out as an instance of close-mindedness? Academics often rely upon authorities when making decisions on moral issues (e.g., the authority of John Rawls when considering matters of distributive justice), although they would likely be uncomfortable characterizing this as reliance upon an authority (even if it is).

Statement 2 reflects a liberal ideological rejection of moral absolutism which, from a liberal ideological perspective, is typically associated with religion. It is also a statement open to multiple interpretations. While reflecting liberal values of toleration and multiculturalism, it could easily be read as a defense of moral relativism, a very problematic view (e.g., female genital mutilation is “right” for societies where it is widely practiced) that bears no clear relation to “open-mindedness.”

Statement 3 is in some ways a concise statement of political conservatism. Edmond Burke, often considered the father of modern political conservatism, wrote repeatedly about the need to “preserve our ancient indisputable laws and liberties, and that ancient constitution of government which is our only security for law and liberty” (Burke Reference Burke and Muller1881/1997, p. 90). Consider contemporary debates over “original intent” in regard to the U.S. Constitution. Many conservatives embrace a strict constitutional originalism based upon an adherence to the principles of the Founding Fathers and reject “judicial activism.” Liberals are more inclined to view the Constitution as a flexible document that should be interpreted in accord with changing circumstances.

Regarding Statement 4: The Oxford Dictionary of Phrase and Fable (Knowles Reference Knowles and Knowles2006) defines a “permissive society” as “the form of society supposed to have prevailed in the West since the mid-1960s (associated especially with the late 1960s and early 1970s), characterized by greater tolerance and more liberal attitudes in areas such as sexuality, abortion, drug use, and obscenity.” On one basic level, we would expect conservatives to be opposed to “more liberal attitudes” (inasmuch as they are conservatives). The differences between American liberals and (social) conservatives on issues such as abortion, drug use, and obscenity are well known.

These are just 4 out of 8 questions in one section of the revised NEO PI-R personality inventory. According to Duarte et al., one explanation for the under-representation of conservatives in social psychology is that liberals are more “open to experience.” What they fail to realize is that this association is circular. It exists because liberal biases are built into the characterization and assessment of personality itself upon which the authors rely.

I suspect that the five-factor model of personality has become something of a sacred cow in psychology. This is unfortunate. The entire inventory is full of all manner of moral and political biases (though it is beyond the scope of this commentary to make this wider case). The liberal biases in the open-to-experience dimension, however, should be clear for all to see. I urge the authors, in line with their own commendable recommendations, and the entire field of psychology, to take note of the liberal ideological biases built into the most widely used measure of personality.