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Charles Lutwidge Dodgson, better known by his pen name Lewis Carroll, was a mathematician who also took an interest in voting.
Dodgson independently rediscovered Condorcet's ideas—apparently without having encountered them—and developed his own method for resolving the dilemmas posed by Condorcet's paradox. Dodgson's method attempts to resolve voting cycles (see the article "The theorist of voting procedures"). It involves determining which candidate could become a Condorcet winner with the fewest adjustments to the votes (an adjustment being defined as swapping two adjacent candidates in a voter's preference ranking).
Consider, for example, an election with three candidates, A, B, and C. If A beats B by 10 votes, B beats C by 5 votes, and C beats A by 2 votes, then A is declared the winner under Dodgson's method because at most 4 adjustments would suffice—the two ballots of voters who prefer C to A, ranked in the worst case as C > B > A—to make that candidate the Condorcet winner, whereas at least 10 adjustments would be needed for B and 5 for C.
In other words, Dodgson seeks to measure the "distance" between an election result and a Condorcet victory by counting how many preference rankings would have to be changed for a candidate to become a Condorcet winner. J.-B. A.
