Yes, you always need to give the reader some optimism: “How to make better decisions.” Except, as Kahneman and Tversky point out, people make their decisions based on heuristics and cognitive biases. Faith that humans can achieve rationality is wishful thinking, but you can’t sell that. Besides Ariely, add Barry Schwartz’ The Paradox of Choice; Sheena Ayengar’s The Art of Choosing; Robert Burton’s On Being Certain: Believing You Are Right Even When You’re Not. Humans have hunter-gatherer brains playing with advanced technology. But let’s pretend it’s all within our grasp, within our capacity to manage our environment, both personal and global. Makes for great self-help articles. Too cynical?