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For $C = 4$, the system has only one stable equilibrium. Because there are no other equilibria to act as separatrices, all initial conditions, regardless of their starting value, will converge to this single positive equilibrium as time progresses.

Conditions: The differential equation is $dz/dt = 4z - z^3 + 4$.; $C = 4$ is greater than the bifurcation threshold C* ≈ 3.079.

For $C = 4$, the system has only one stable equilibrium. Because there are no other equilibria to act as separatrices, all initial conditions, regardless of their starting value, will converge to this single positive equilibrium as time progresses.

Conditions: The differential equation is $dz/dt = 4z - z^3 + 4$.; $C = 4$ is greater than the bifurcation threshold C* ≈ 3.079.