Interestingly, there are even information-theoretic reasons to prefer 3-way branching representations, as explained in this article about "Base 3": http://www.

Interestingly, there are even information-theoretic reasons to prefer 3-way branching representations, as explained in this article about "Base 3": http://www.americanscientist.org/issues/id.3268,y.0,no.,content.true,page.1,css.print/issue.aspx http://www.americanscientist.org/issues/id.3268,y.0,no.,cont... Base 3, on the other hand, does have a genuine mathematical distinction in its favor. By one plausible measure, it is the most efficient of all integer bases; it offers the most economical way of representing numbers. (Culturally, I think any reduction to 2 choices calls to mind simplistic patterns of 'only 2 directions'/1-axis/1-line, or 'good'/'evil'. You expect one option to dominate. As soon as you reach 3 choices, people recognize that evaluation may require 2 or more dimensions of balancing, using curved preference functions and more thought.)