Gray reasoned that Carmax, with nine years of experience running its stores and a record of solid profitability, ought to be the leader in this emerging business.

FORBES: Unsung outperformers

This led Dr Gray and Dr Wegner to wonder if the reverse, discovering a lack of experience in a place where it was expected, might prove just as upsetting.

ECONOMIST: Why androids are scary

Undulating paths lead through 2, 700 gray columns of varying height, making a visit to the memorial a suitably unsettling experience.

CNN: Berlin: What to see