The Guinness Book of World Records was started to settle an argument.
About what?

Question

Accepted Answer

Whether the golden plover was Europe’s fastest game bird — an unsettled pub bet in 1951. — Sir Hugh Beaver, Guinness Brewery’s MD, realised no reference book had the answer. He hired twin brothers to write one. It became the world’s bestselling copyrighted book.

The Guinness Book of World Records was started to settle an argument. About what?