Conversation so far:
What were Gottfried Wilhelm Leibniz's ideas about?
As a representative of the seventeenth-century tradition of rationalism, Leibniz's most prominent accomplishment was conceiving the ideas of differential and integral calculus, independently of Isaac Newton's contemporaneous developments.
Was Gottfried Wilhelm Leibniz spiritual or religious?
In philosophy, Leibniz is most noted for his optimism, i.e. that our universe is, the best possible one that God could have created
Did others agree with Gottfried Wilhelm Leibniz?
idea was often lampooned by others such as Voltaire.

Question: Was he optimistic because of his beliefs and that he saw a purpose in things such as religion and philosophy?
Self-contained rewrite: Was Gottfried Wilhelm Leibniz optimistic because of his beliefs and that he saw a purpose in things such as religion and philosophy?