Supermajority rule gave southern Democrats an effective veto over any presidential nominee for many years, until the rule's abolition at the 1936 Democratic National Convention. A majority vote, or more than half the votes cast, is a common voting basis. Instead of the basis of a majority, a supermajority can be specified using any fraction or percentage which is greater than one-half (i.e., 50%). It can also be called a qualified majority. Common supermajorities include three fifths (60%), two thirds (67%), and three quarters (75%). A two-thirds vote, when unqualified, means two-thirds or more of the votes cast. This voting basis
Rule of thirds as a rule for the proportion of warm to cold colors in a painting, and attributes to Smith the expansion of that rule to all proportions in painting: Sir Joshua has given it as a rule, that the proportion of warm to cold colour in a picture should be as two to one, although he has frequently deviated therefrom; and Smith, in his "Remarks on Rural Scenery," would extend a like rule to all the proportions of painting, begging for it the term of the "rule of thirds," according to which, a landscape, having one third of land, should have