Interesting article, thank you — gives me something to think about as I tend to consider myself an eternal optimist. I think the main thing about unhealthy vs healthy optimism is attachment — when we are so attached to the IDEA of a certain outcome that we aren’t flexible enough to change our actions and make adjustments to our plans as needed, that’s when “unexpected” problems can often arise. I believe it is indeed important to consider both sides of the coin — to prepare for the worst but trust in the best.