Introduction to Adult Development
Adult Development made as simple as possible
The toddler who impulsively splashes in a puddle, without the ability to foresee that they will suffer being wet. The young child who talks about dinosaurs endlessly, without consciousness that others are not interested. The teenager who works out intensely in a sport they don’t like very much because of the pull of the social group. A doctor so committed to patient autonomy that they don’t push back on poor patient choices.
The patterns of interaction of each of these are characteristic ways of seeing the world in human development. Each of them has a distinctive center of gravity in how they see the world with respect to what determines their actions. Are they acting without awareness of their own mind, with awareness of their own mind, with awareness also of the minds of people they know, as participants in a social system that reaches beyond their circle of face-to-face relations, or in a context of participating in multiple social systems that cannot be reconciled by a supervening one? In other words, what are their characteristic forms of subjectivity?
I and others use the term “Adult Development” to refer to this dimension.
The following stages each require the predecessor to be sufficient to serve as a base for the next stage.
It: actions are felt to be determined outside of any sense of “I”. “Anger came over me, and I just lashed out”. This is the default state we all start with as infants.
I: The felt sense is that I determine my actions. “Because I want to”. The “It” stage always precedes the “I” stage as a matter of biological development. The new capacity here is a locus of personal control, previously unknown.
We: The “We” of everyday relations feels determinative of my actions. “That’s what we do”. This stage presupposes an “I” that has become subordinate to “We”. For the first time, the capability arises of comprehending that others may see things differently. In the previous stage, the child who talked to everyone about dinosaurs did not yet have the capacity to comprehend deeply that others have different minds and tastes than he did.
Us: My actions are determined by identification as a participant in a way of life, whether a workplace culture, a religious culture, or a rational system of principles. “This is what people like us (Christians/Armed Forces Members/Nietzscheans) do”. This is an expansion from the personal “we” in the previous stage to the extended “us”: a network of relationships and roles that is not limited to face-to-face relations. The capacity to comprehend that particular other people have different minds has expanded to the capacity to take on a mindform, a systematic way of seeing the world.
This: My actions are determined by the unbounded context that encompasses all I am aware of. “This is what the situation calls for”. Context becomes determinative only when one holds multiple identities that cannot be reconciled, forcing the situation to become the context for trade-offs that cannot be rationalized. Entrepreneurs, for example, often find themselves juggling the human concerns of employees, business concerns, and personal concerns, with no available method to reconcile these.
It, I, We, Us, This: at some point in our lives, these can all become active simultaneously, with a distribution between them that is always slowly changing.
Note that someone with a center-of-gravity in an earlier stage can still mimic the behavior of a later stage skillfully, and that someone with a center-of-gravity in a later stage may appear to be acting as if from an earlier stage. Occasionally, the earliest glimmers of the final stage appear during the mid-teen years. Once the final stage is available, we can turn from the question of “is this an available pattern of interaction?” to “what is the distribution of patterns of interaction?”
The capabilities of each stage rest on a “good enough” foundation of the prior stage; while less common, it is certainly possible to have a lumpy distribution across stages. Development can also lag in some domains compared to others (intimate relationships vs. work, for example).
To what degree we can support natural processes of adult development, advance them, or even accelerate the center-of-gravity is an open question. An example of support is a positive peer group that provides a circumstance for someone to consolidate moving from self-centeredness to group-centeredness. An example of advancing would be to notice that an employee is ready to take on responsibilities for making impactful decisions that have no clear “right” solution, and to place them in that role.
We can learn much about how our own and others’ forms of subjectivity are determinative of action, but such assessments, being subjective, remain inherently imprecise.
Related explorations:
Articles
Adult Development: The Return: There is more to discover where you have already trod
Adult Development as Affordances and Aesthetics: The orders of adult development
Notes
Extending Kegan: Dissolution of the Framework


This has helped me understand the difference between 1 and 2, but I'm not sure about "Us" as the term for stage 4.
Given the explanation and my existing knowledge, I see how it links up, but I wouldn't call it a natural handle for the systemic/rational stage.
Your post inspired another epiphany! I'm uncomfortable with the term "stages of development" (adult or otherwise) because, for me, "stages" almost intrinsically connotes the concept of ranking into higher and lower, and the idea that the some stages are merely temporary ladders to be discarded (ie, merely means to an end) .
I finally thought of a term that I find more comfortable: branches of evolution (or perhaps for more backwards compatibility "branches of (adult) development"). Though the concept of branching can also connote ranking and instrumentality, for those who study evolution more deeply such connotations are no longer as strongly evoked. The human branch is no "higher" than other primate branches (nor the bacterium branch for that matter) even though the human branch emerged from other branches.
It also reinforces that as branches, It, I, We, and Us are forms of life every bit as worthy as continuing *as is* as the This branch. In other words, there is no universal context from which to assert that transforming from It to I is healthier or better. In various contexts, being a toddler is just as worthy as being a child, which is just as worthy as being a teenager, which is just as worthy as being an adult. And in various contexts, it may be healthier to transform from teenager to adult, but in others it may be healthier to remain a teenager for longer durations or even throughout the rest of one's life; or perhaps even transform from adult to teenager, not just temporarily, but for the remainder of one's life.
Evolution teaches us that neoteny (retaining more juvenile forms rather than developing into adult forms) can even explain the emergence of humanity itself! See https://en.wikipedia.org/wiki/Neoteny_in_humans#Specific_neotenies:~:text=Bruce%20Charlton%2C%20a,a%20neotenous%20trait.
For all these reasons "branches of development" and "branches of evolution" resonate more deeply for me than "stages".