The butterfly catastrophe has a single state variable [a public policy
decision], with four control variables to interpret [the Popcycle]: for
example, [ Joy / Sadness, or Reward / Punishment ] as conflicting
variables in the normal-splitting
plane. The compromise will be represented by points on the middle sheet,
and since it is the butterfly factor which causes this sheet to appear we
shall want
to identify this factor with whatever we believe is chiefly responsible
for making compromise possible. One plausible candidate is
time
.
P. T. Saunders, An Introduction to Catastrophe Theory.