Full Idea
Order must be defined by means of a transitive relation, since only such a relation is able to leap over an infinite number of intermediate terms. ...Without it we would not be able to define the order of magnitude among fractions.
Gist of Idea
The definition of order needs a transitive relation, to leap over infinite intermediate terms
Source
Bertrand Russell (Introduction to Mathematical Philosophy [1919], IV)
Book Reference
Russell,Bertrand: 'Introduction to Mathematical Philosophy' [George Allen and Unwin 1975], p.38