I've always loved Mulder's quote from Aubrey, which Scully also repeats in Paper Hearts:
"Dreams are the answers to questions that we haven't yet figured out how to ask."
It rings even more insightful now that I understand the language of dreams better. The language that Chris Carter uses in his storytelling. The truth that Mulder pursues on The X Files doesn't really involve shadow men and aliens, but matters of his own heart. And Scully's journey flows like water, concurrent.
Triangle belongs to a subheading of XF episodes classified by The K Files as Chris Carter's Fairytales. These new myth stories propel our heroes through a journey more internal than external, a journey of the heart.
In Post Modern Prometheus, Mulder and Scully traversed the special world of rural Indiana, comic books, and a deconstructed Mary Shelley. In Triangle, Mulder travels (elaborately) from DC to the waters of the Bermuda Triangle, and then all the way into World War II and the dark terrain of the psyche.
Triangle is Mulder's dream. He answers his own question, and the answer is always Scully.
Review our findings from sixth season jewel, Triangle