Drug users are Modernists who despise Classicism

[Dante Alighieri]

Dante, if you're going to be as verbally grandiose as you are, you need to know that "it's" = "it is."

"Its" is the possessive prounoun form you want in your phrase above, "its guiding principle."

This will come in handy--and be more impressive--in further debates.

Logically of course, that renders my argument obsolete.