456 v. AFFECTI vE PROCESSES
social hierarchy. Each dynamic pattern of 
emotional expression configures a particu -
lar kind of relationship.
Beyond the Basic Six: 
Expanding the Taxonomy of Emotions
The second major development with wide -
spread implications for personality psy -
chology is the dramatic increase in distinct 
emotion constructs that are theoretically 
grounded, and the focus of a strong and 
growing body of science. Fifty years ago, 
Ekman and Friesen’s (1968, 1971) research 
on facial expression with the Fore tribe in 
the highlands of New Guinea launched the 
contemporary scientific study of emotion. In 
so doing, it oriented the field to the “Basic 
Six” emotions whose prototypical expres -
sions were included in those studies: anger, 
disgust, fear, sadness, happiness, and sur -
prise. The Ekman and Friesen discoveries 
would frame a first generation of research 
on emotion, which has investigated modali -
ties, universals, and cultural variations in 
emotional expression (e.g., Keltner et al., 
2016), examined emotion-  related physi -
ological activation in the peripheral nervous 
system and the brain (e.g., Kragel & LaBar, 
2016; Kreibig, 2010; Levenson, Ekman, & 
Friesen, 1990; Lindquist, Wager, Kober, 
Bliss-  Moreau, & Barrett, 2012; Nummen -
maa & Saarimäki, 2017), and characterized 
the eliciting appraisals, action tendencies, 
and subjective qualities of these six emotions 
(Lench et al., 2011). The Ekman and Friesen 
discoveries, and the theoretical and concep -
tual issues surrounding the interpretation 
of their findings, would also fuel consider -
able and lasting debate about the nature of 
emotion (e.g., Barrett et al., 2007; Russell, 
1994).
Although the Basic Six remain “the” emo -
tions as portrayed in textbooks and the pop -
ular press, affective science now addresses 
a much wider array of emotions. There is 
considerable irony in the field’s perseverative 
focus on the Basic Six, for Charles Darwin, 
whose 19th-  century work on emotional ex -
pression provided the inspiration for mod -
ern studies, richly detailed the patterns of 
expression for over 40 emotion-  like states 
(Darwin, 1872/1998; Keltner, 2009). The Basic Six are a narrow slice of human emo -
tion. One might think of them—  particularly 
fear, anger, and disgust—  as the emotions of 
individual self-  preservation, with primary 
adaptive functions that involve avoiding or 
escaping threats to life and limb. The Basic 
Six includes just one broad and vaguely de -
fined positive state—  happiness. Although 
English-  language speakers consider “love” 
and “desire” as prototypical emotion states 
(Acevedo & Aron, 2009; Shaver, Schwarz, 
Kirson, & O’Connor, 1987), and emotional 
responding figures prominently in Bowlby’s 
(1969) theories of attachment, parental 
bonding, and sex, the Basic Six includes no 
states emphasizing emotional responses to -
ward close relationship partners. The Basic 
Six also excludes self-  conscious emotions, 
such as embarrassment and pride, that are 
vital in navigating the codes and hierarchies 
of human social living (Keltner & Buswell, 
1997; Tangney & Fischer, 1995; Tracy et al., 
2014).
Functional analyses—  theoretical defini -
tions positing the evolutionary context and 
adaptive function of each specific emotion— 
play a crucial role in generating hypotheses 
for empirical research (Shiota, 2021). As long 
as the emphasis in these analyses remained 
on intrapersonal or purely individual-  level 
functions, the Basic Six covered the terrain 
reasonably well, and most 20th-  century sci -
ence on emotion was limited to these states. 
As we have noted, however, a social func -
tionalist account broadens greatly the range 
of emotions for which a sound functional 
analysis can be performed. For example, a 
rich literature now maps distinctions among 
“self-  conscious” emotions including embar -
rassment, shame, guilt, and pride (Keltner 
& Buswell, 1997; Tangney, 1990; Tracy et 
al., 2014). Inspired in part by Fredrickson’s 
(1998, 2001) broaden-  and-build theory, 
which emphasizes the role of positive emo -
tions in acquiring crucial social and infor -
mational, as well as material, resources, 
scientists have begun to map conceptual 
and empirical distinctions among positive 
emotions such as amusement, awe, content -
ment, enthusiasm, gratitude, interest, love, 
and relief (e.g., B. Campos, Shiota, Keltner, 
Gonzaga, & Goetz, 2013; Cordaro, Keltner, 
Tshering, Wangchuk, & Flynn, 2016; Kelt -
ner & Haidt, 2003; McCullough et al., 2002; 