In a specific sense, everything in our reality manifests an intention. At some scale, those intentions appear trivially primitive: a rock "intends" to be hard; water "intends" to be liquid. But at the scale at which their form becomes manifest, these intentions can become, to those that study them, wondrous and magical. The hardest rocks manifest crystalline structures of great intricacy. A crystal can be thought of as a manifestation of the properties of the chemical and thermodynamic conditions of its growth: it manifests the "intention" of those conditions to produce a crystal, and under those conditions no other crystal can materialize. Once formed, that crystal acts as a seed for growth even under conditions that would normally manifest other crystalline shapes.
Human beings, we typically like to think, are conscious and intelligent in the management of their intentions. Of course, in some circumstances - such as in conditions of war, famine or plague - those choices may be severely constrained: we can choose to either live at others' expense, or we can choose to die. Infants in those circumstances may never progress much beyond the crude level of the crystal: they are brought into the world through the chance of circumstance, and die.
I don't mean to be flippant about such tragedies, but as we are composed of matter, it appears inevitable that such conditions will continue to recur. The choice to destroy others to survive is an emotional choice. Rationally, we would agree to preserve the best and brightest in the culture. This is rarely what happens: only those trained to the service of a higher ideal are likely to make this sacrifice. Normally, the descent to the emotions of the survival imperative is accompanied by a complete loss of rational control, and people will act like beasts. The resulting conditions are not supportive of the attainment of higher human aspirations.
In more successful circumstances, the child will be nurtured at least until he or she is able to be a productive contributor to the community. In primitive cultures, this may be as early as eight or so, when the child can manage animals. In modern social elites, it may be as late as 30, after completing a rigorous qualification for research in academe.
At what point does choice become available to an active member of the community? In primitive cultures, usually once the child is able to escape the coercive influence of his or her parents. (For those that believe there is a gender imbalance: we'll get into sexual politics later.) In advanced cultures, only when the earnings capacity of the child becomes sufficient to sustain an independent lifestyle. This can be anywhere from 13 to 40 years of age.
So what do we do with this freedom? Well, that depends upon the refinement of our judgment. Judgments are something that we start to make once our guardians determine that we have mastered a skill, and leave us without supervision. In the worst case, that time alone is undirected: the outcomes of the child's endeavors are never subjected to mature evaluation. His or her judgments are not refined, and the child may be tempted to destructive action. ("The devil makes work for idle hands.") In the best case, as with children schooled at home by a permissive and constructive parent, the child makes judgments as often as possible, and receives direct feedback frequently, until his or her judgment regarding the need to have guidance becomes sufficiently refined that he or she can be trusted to seek guidance independently.
What is the basis for making judgments, and refining that capacity? It is instructive to consider the processes evolved by our culture to control the natural tyrannies.