Trace Determinant Plane Coffee Mug

We know what you're thinking: oh, if only everything in life were as simple as two dimensional systems of linear differential equations with constant coefficients. They are indeed, as they say, a done deal. A known quantity. Stick a fork in it, you! Compute the trace and determinant, refer to your handy LabKitty Trace Determinant Plane product, and Bam! You know what the system will do. Source, sink, spiral in, spiral out, or saddle (also: centres, which we're treating as a spiral w/ zero real part). That's it. Those are the possibilities. Nothing else. No surprises. Nowhere in there will you find "break all your dishes" or "shave your cat" or some other trip to crazytown. This is why eigenvalues are superior to interpersonal relationships in almost all things. Customisable.