A Stanford course on iTunes U, "Literature in Crisis," includes two lectures on Candide: here and here. These are by Martin Evans, Chair of the English Department.
As a literature guy, he has a bit to say about satire: why it flourished in this age in particular (because of the relative peace and stability, which explains why it's rampant now too). He also has some interesting points to make about Voltaire's biography. The bulk of the lectures is taken up by a consideration of the various positions on the problem of evil:
-The totalist position represented by Leibniz (and Pangloss in the book) which says that the apparent evil of the world really is part of a good whole that we as finite creatures can't perceive. Evans states that Voltaire was responding in Candide to "An Essay On Man," by Alexander Pope, which would help to explain why we don't see Voltaire tussle with the specifics of Leibniz's arguments. He also cites Voltaire's exchange with Rousseau about the Lisbon Earthquake. Voltaire dismisses optimism as a "discouraging fatalism." At the beginning of the second literature, Evans sets out his theory (which I cited in the episode) that the optimist's God is comparable to the narrator of the book: he just doesn't care about human suffering.
-The Manichaean position (represented by Martin in the book) that says that God is only one of two primal forces in the world, the other of which is evil. You might think that this represents Voltaire's view, but looking at other things (Evans quotes a letter Voltaire wrote), it's evident that he thought this view was nonsense.
-The view that evil is caused by Original Sin, that the world is not good because we screwed it up, and that curse (which can include natural disasters, not just human sinning) is what's still haunting us today. Evans argues that this is Voltaire's view, and uses the fact that Candide makes such heavy use of the Garden of Eden imagery as an argument. The whole book can be read, Evans says, as an account of what happens to humanity after leaving the garden. Moreover, Evans reads the "tend your garden" part and the aversion to metaphysical speculation as evidence that Voltaire did think there was a divine plan, and that we should just stop questioning it and do our duty according to this plan (Evans quotes Tenyson: "Theirs not to reason why, theirs but to do and die."). Evans sees this as a very negative message, about as far from the Enlightenment as one can get.
-Mark Linsenmayer
candide is by far my favorite proto-existential novel. I think the idea that satire is most prevelant during times of peace and stability is a really interesting however, I think reading Candide in relation to Camus’ The Fall (another novel that emplys garden of eden imagery) and ‘The Myth of Sisyphus’ would bear impressive results insofar as an existential or absurd reading of this novel will tend to eschew notions of the ‘negativity’ of satire and will instead focus on the transcendental laugh that makes up a large and dissonant part of the novel’s (narrator’s) tone (and leads Evans to say that the narrator ‘just doesn’t care’ about human suffering) and the sublime ‘acceptance’ or ‘revolt’ (referring here to the Myth of Sisyphus) of certain characters (thinking here especially of the old woman).