 26. Naturalizing the Self 569
a parent or peer reinforces the feeling that 
the experience happened to him or her and 
supports a self-  concept that extends into the 
past. Importantly, children’s ability to hold 
dual representations in mind also increases 
during middle childhood. This allows chil -
dren to become aware of patterns across 
their self-  representations, from which they 
extrapolate higher-  order information about 
who they are. For example, a child may infer 
that he or she is an athletic person based on 
self- representations including “I play soccer 
well,” and “I ran fast and won a medal at the 
race.” Critically, viewing oneself as athletic 
represents a higher-  order generalization or 
trait, which results in a self-  concept that is 
more coherent, organized, and complex, as 
well as more consequential for future behav -
ior. As children develop more complex and 
abstracted self-  representations, they also 
begin to form stable evaluations  of their 
overall worth as a person, providing reliable 
and valid reports of their global self-  esteem 
by around age 5 (e.g., Harris, Donnellan, & 
Trzesniewski, 2018; Measelle, John, Ablow, 
Cowan, & Cowan, 2005).
Late childhood to early adolescence (ages 
9–14 years) is a period of increasing com -
plexity and organization for the developing 
self- concept. Some of these changes arise be -
cause children become more aware that oth -
ers are evaluating them, and consequently 
engage in more frequent social comparisons 
(e.g., “I am smarter than all the other kids 
in my class”; “I am less attractive than my 
friends”). There is also an increase in self- 
conceptions concerning interpersonal traits 
(e.g., “I’m a caring friend”) due to the in -
dividual’s increased focus on peer and ro -
mantic relationships. Important changes 
in self-  concept differentiation and abstrac -
tion also occur during this period. Differ -
entiation occurs when individuals perceive 
themselves differently across contexts, such 
as having an academic self  that is distinct 
from their social self . For example, they may 
view themselves as irresponsible in school 
but as dependable and trustworthy with 
friends. Abstraction occurs when individu -
als attempt to make meaningful inferences 
about who they are based on an integration 
of traits. For example, a child may infer that 
she is a conscientious person because she 
sees herself as responsible, punctual, and organized across contexts. Abstraction rep -
resents a significant advance in self-  concept 
development, allowing the individual to or -
ganize self-  concept content in ways that lead 
to greater coherence.
In late adolescence, increases in abstract 
thinking ability and introspection lead to 
further differentiation of the self-  concept. 
Importantly, individuals begin to differen -
tiate between their actual and ideal selves. 
They consider not only what they want to be 
when they get older but also which psycho -
logical traits and abilities they would like to 
possess, and which future goals they would 
like to achieve. This period is therefore 
marked by an increasing orientation toward 
the future self, which promotes positive 
change by motivating individuals to engage 
in behavior aimed at achieving future goals.
By early adulthood, most individuals have 
developed the cognitive capacities needed 
to support a self-  concept that is coherent, 
stable, complex, and abstract. However, this 
does not mean that people’s self-  conceptions 
do not continue to change across the lifes -
pan, just that the basic cognitive system 
underlying self-  conceptions is fully mature 
by early adulthood. As people go through 
life and face new challenges and opportuni -
ties, and experience successes and failures, 
they learn more about themselves and, in 
many cases, change their self-  conceptions. 
However, these changes are the result of 
new information about the self, not further 
maturation of the underlying cognitive ca -
pacities that support the development of 
self- conceptions. The only exceptions to this 
developmental sequence are changes in the 
underlying cognitive system due to a severe 
mental health disorder or neurological dam -
age, both of which can radically alter a per -
son’s self-  concept.
In summary, the development of the self- 
concept (the “Me”) follows a specific time 
course that corresponds to the development 
of a set of basic cognitive capacities. Paral -
leling this developmental sequence, system -
atic changes also occur in the overall valence 
of the self-  concept (i.e., self-  esteem). Mean 
levels of self-  esteem tend to increase slightly 
from the preschool years to middle child -
hood, plateau (but do not decline) in early 
and middle adolescence, increase sharply 
from around age 15 into young adulthood, 