If the object is mostly rotating along its third axis, so | ω ω 3 | ≫ ≫ | ω ω 1 | , | ω ω 2 | , we can assume ω ω 3 does not vary much, and write the equations of motion as a matrix equation: d d t [ ω ω 1 ω ω 2 ] = [ 0 − − ω ω 3 ( I 3 − − I 2 ) / I 1 − − ω ω 3 ( I 1 − − I 3 ) / I 2 0 ] [ ω ω 1 ω ω 2 ] which has zero trace and positive determinant, implying the motion of ( ω ω 1 , ω ω 2 ) is a stable rotation around the origin—a neutral equilibrium point. Similarly, the point ( ω ω 1 , 0 , 0 ) is a neutral equilibrium point, but ( 0 , ω ω 2 , 0 ) is a saddle point.