The Juxtaposition Cross of Principles is named for Gate 49 and Gate 4. Human Design reads Gate 49, from Hexagram 49, Revolution, as the sense of what is acceptable, deciding whether an arrangement continues or is broken off, and Gate 4, from Hexagram 4, Youthful Folly, as the mind's habit of proposing answers to questions still open. Juxtaposition Crosses are set apart from the Right Angle and Left Angle families, reserved for the four line one profile, and read as fixed almost past the point of alternative.
Its design half is Gate 14 and Gate 8. Gate 14 sits in the Sacral and is read as the fuel that directs resources and effort toward work that feels worth doing; elsewhere it pairs with Gate 2 in the channel of the Beat. Gate 8 sits in the Throat and is read as the urge to contribute an individual style and to stand publicly behind something that matters; it pairs with Gate 1 in the channel of Inspiration.
So the cross reads as a judgment of what is acceptable, Gate 49, held against a mind proposing answers, Gate 4, while beneath it sacral fuel, Gate 14, drives a public, individual contribution, Gate 8. The numbers are inherited from the I Ching; reading them as one cross belongs to the modern reading, not the classical one.