Unanimity
The unanimity principle is a Voting Theory principle. ‘‘Unanimity’’ means “agreement reached by all people”.
Using Voting Theory Relations for $N = 2$ we define Unanimity as:
- if $x \ P_1 \ y$ and $x \ P_2 \ y$ then $x \ P \ y$
- or $x$ is globally preferred to $y$ if both voters vote for $x$
It follows from two principles
- Non-Imposition and Monotonicity
- shown in Arrow’s Impossibility Theorem (Unanimity consequence)
If a candidate $a$ is always preferred by the majority to $b$, then we can say that $b$ is dominated by $a$ and never consider $b$ again
Dominance
The same concept in different disciplines is also often called Dominance