assuming this is the definition "few fundamental principles that may be combined without unneccessary restrictions"
from a syntactic view of scripting languages:
would perl have a low orthagonality, because it has so many equivelant syntactical ways of expressing the same action? ie more ways to do it than any one person usually knows about
would python have a high orthagonality because of it's enforced white-space based scoping? ie only one way to do it
would any scripting language that isn't compiled into assembly code be considered even basically orthogonal, since such a language is run through an interpreter written in another language, and as such derives it's structures from things completely different than then functionality the coder sees?
would php be considered more orthagonal because it's versions of arrays and hash tables are identical?