Some articles on valid coops:
... declare Soureh (or knock) if he has four valid coops and believes that his opponents do not ... If he believes that an opponent has four valid coops or is close to having four valid coops, it is better for him to wait until the opponent knocks ... his hand if the replacement would give him four valid coops ...
Famous quotes containing the word valid:
“It is not enough that France should be regarded as a country which enjoys the remains of a freedom acquired long ago. If she is still to count in the worldand if she does not intend to, she may as well perishshe must be seen by her own citizens and by all men as an ever-flowing source of liberty. There must not be a single genuine lover of freedom in the whole world who can have a valid reason for hating France.”
—Simone Weil (19091943)