Consensus is the decision-making standard used by several collaborative governance projects to determine if a proposal has enough support to become policy. Broadly defined, it is a general agreement among the community, or at least a lack of dissent. It is the foundation of the third and fourth basic principles of the Metagovernment project. See the Wikipedia article on Consensus.
The precise definition of consensus within this project is not yet clearly defined (see Talk:Consensus). In smaller communities, it may be defined as the complete lack of dissent. However, in very large, very diverse groups, this definition might not be practical (at least until people get more accustomed to using this standard). The scoring system used by Metascore might define a threshold at which consensus is defined which is less than unanimous consent. In initial versions of Metascore, we will likely use a variable for this threshold, and see if real-world use can find a reasonable mathematical formula. However, we may find that this is not necessary. We intend for Metascore to be implemented first in small communities, and to gradually grow to larger ones. As that process develops, people may simply find that full consensus is an appropriate standard even for very large groups.
Effectiveness of consensus decision-making
While consensus decision-making may at first glance appear to be an impractical way to get things done, it has been proven effective in even large groups. See the Wikipedia article on consensus decision-making. A notable example is the American Quaker community, which came to a unified consensus against the institution of slavery seventy years before the rest of the United States even began to take action against slavery. It can be said that the Quakers are a unified community and thus can more readily achieve consensus, but the same example shows otherwise: before that time, Quakers regularly practiced slavery, and it had taken them about eighty years to come to that consensus against the practice.
A common question asked is: "What if a decision absolutely has to be made, but no consensus can be reached?" The simple answer is: if there is no consensus about a solution, then is there really an urgency to the situation? If there truly is urgency, then people will simply have to work harder to achieve a consensus. They might even have to degrade to a compromise, though it is hoped (and encouraged through the mechanisms of Metascore) that instead they can find a synthesis which brings opposing views together to a consensus. See also Talk:FAQ#Emergency_Planning.
- The Wisdom of Crowds - A book proposing that large groups make better decisions than individuals or small groups.