What is the most important quote in Candide?

One of the most important quotes in Candide is "All is for the best in the best of all possible worlds." This phrase reflects the optimism and naivety of Pangloss, who espouses the philosophy of Leibniz that suggests everything happens for a reason and is ultimately for the best. This quote sets the tone for the satirical exploration of optimism and the idea that blind faith in an ordered world can lead to complacency and disregard for real-world suffering.