Noise, according to Nobel-prize winning economist Daniel Kahneman, is the unwanted variability that can cloud judgment and impact decision making. We can make different decisions when influenced by noise, such as when we are upset, tired or hungry compared to calm, rested or well-fed. Kahneman shows how doctors give drastically different diagnoses to identical patients as a result of this noise. Most of the time, we are unaware of the noise and neglect it. Yet, by reducing it we can make better decisions.