Habit converts imposed external constraint into self-chosen desire for what is

Evidence

Thus habit is revealed as a process through which man ends by willing or choosing what came to him from outside. Henceforth the will of the individual does not need to oppose the pressure of the external world; the will learns gradually to want what is. The ideal ceases to appear as something which ought to be, which ‘might be but is not yet’. To the degree that the objective merges with the movement towards it, the ideal is achieved. — Catherine Malabou, The Future of Hegel, 580

Categorization

• XREF: Directly addresses the reader’s plasticity question: habit is the mechanism by which receptivity (taking in what comes from outside) tips into agency (willing it). Also connects to Spinoza’s conatus and to later French theory of subject formation (Althusser’s interpellation, Foucault’s discipline).
• DEFINE: Gives a precise definition of habit as the conversion of passivity into voluntary choice — the key hinge the reader is seeking.