What is self-consistency and how does it differ from a single chain-of-thought answer?

Self-consistency samples multiple independent chain-of-thought reasoning paths (using temperature > 0) for the same question, then takes a majority vote over the final answers rather than trusting one greedy decode. The intuition is that a correct answer can be reached by many different valid reasoning routes, while errors tend to be idiosyncratic, so the most frequent answer is more likely correct. It notably improves accuracy on arithmetic and commonsense reasoning benchmarks over a single CoT sample. The tradeoff is cost: you pay for N generations (often 5 to 40) and need answers you can aggregate, so it fits tasks with a discrete final answer. It does not fix systematic biases shared across all samples.