Buying an extra cup of coffee means less money for a cup of tea. It also means less coffee for the next person, it will change the prices of milk and sugar and effect the countries which make the coffee beans for your cup of joe. Betsey Stevenson and Justin Wolfers teach us about how our decisions are interlinked, and how this can help you to make better decisions.Co-host: Nastaran Tavakoli-Far. Editor: Alastair Elphick. A Modulated Media production.