It keeps us safe and it makes us miserable, but humans are hardwired for negativity. Two-thirds of the neurons in the brain’s amygdala are attenuated for negativity, quickly storing bad memories while positive cells take their time. Our words are mostly negative, our dreams tilt toward anxiety. This may have protected early humans when they were as likely to become dinner as enjoy it, but now it’s threatening our loves, livelihoods and peace. Today’s scientists are trying to determine if we should deny or embrace our dreary orientation.