Sign up for the Smarter Faster newsletter A weekly newsletter featuring the biggest ideas from the smartest people For nearly all of human history, fire was our only source of artificial light. Difficult to make and challenging to safeguard from wind and rain, fire was our first window into the darkness of night. Fire and the artificial light and radiant warmth it produced changed everything and helped catapult humans toward the modern age.We have forgotten how unrelentingly dark the pre-industr...