 None of this should be surprising. Hume may have endorsed just one species of cause—efficient—but final and formal causation did not die with the advent of mechanistic science and philosophy in the seventeenth century. Besides Leibniz, Gassendi, Boyle, and Newton all accommodated final or teleological causation in their systems. Spinoza is really the only known philosopher in the seventeenth century who truly has no place for final causation in his philosophy, except in the sense that artifacts have final causes (e.g., chairs serve a purpose and carpenters create them in part to achieve that purpose). On the other hand, Spinoza probably does endorse formal causation in his metaphysics of substance.