Why do they use white to show that they're giving up?

Question

Why do they use white to show that they're giving up?

Answer 1

It was first used by the Han dynasty in the Eastern part of China sometime around 200 as a sign of surrender.  Not much is known about how it went on to become the international sign of parley, cease fire and or surrender but it is now recognized in that capacity.

Answer 2

All countries, political parties, public interest groups, have a flag, an emblem, a symbol, that identifies them. When they show a white flag, t-shirt, table cloth etc., it means that they have laid down their own symbol and want their opponents to know that they are ready to surrender.

Answer 3

who's 'they' and what are they giving up on?