The middle point y = 0 {\displaystyle y=0} is unstable, while the other two points are stable. The direction of change of y ( t ) {\displaystyle y(t)} over time depends on the initial condition y ( 0 ) {\displaystyle y(0)} . If the initial condition is positive ( y ( 0 ) > 0 {\displaystyle y(0)>0} ), then the solution y ( t ) {\displaystyle y(t)} approaches 1 over time, but if the initial condition is negative ( y ( 0 ) < 0 {\displaystyle y(0)<0} ), then y ( t ) {\displaystyle y(t)} approaches −1 over time.