Duration. The Sequence of the Hexagrams says: The way of husband and wife cannot fail to endure; hence it is received with Duration. Duration means long-lasting.
Influence (Wooing) is the way of husband and wife, and husband and wife remain unchanged throughout life; hence Influence (Wooing) is followed by Duration.
In Influence (Wooing), the youngest son is below the youngest daughter, placing the man beneath the woman, which conveys the meaning of mutual influence between male and female.
In Duration, the eldest son is above the eldest daughter, placing the man in honor and the woman in humility, which is the constant way of husband and wife in the household.
In terms of mutual feeling, youth brings intimacy; in terms of hierarchical order, seniority demands solemn propriety. Thus Dui and Gen form Influence (Wooing), while Zhen and Xun form Duration.
The man being above the woman, the man moving on the outside and the woman complying on the inside—this is the constancy of human principle, hence it is Duration.
Moreover, the firm above and the yielding below, thunder and wind joining together, gentle yielding and moving, the firm and the yielding all corresponding—these are all meanings of Duration. Duration. Success. No blame. Advantageous to be steadfast.
It is advantageous to have somewhere to go. Duration means constancy and longevity. The way of duration can bring success; only when enduring and able to succeed is there no blame. Enduring without being able to succeed is not a way that should be endured, and blame will follow.
For instance, when a noble person endures in goodness, that is a way worth enduring; when a petty person endures in evil, he loses the way worth enduring.
The reason duration can achieve success is due to steadfastness and correctness; hence it says 'advantageous to be steadfast.' What is called duration refers to a way that can endure, not holding rigidly to one corner without knowing how to adapt.
Hence it is advantageous to have somewhere to go; only by having somewhere to go can one endure. Being fixed admits of no constancy. Moreover, in the constant and enduring way, where would one go that is not advantageous?
The Commentary on the Judgment says: Duration means long-lasting. Duration carries the meaning of enduring long. The hexagram talent possesses these four qualities, fulfilling the meaning of Duration.
'The firm above and the yielding below' means that the initial line of Qian ascends to occupy the fourth, and the initial line of Kun descends to occupy the initial, with the firm line ascending and the yielding line descending.
When the two lines exchange places, Zhen and Xun are formed; Zhen above and Xun below also represents the firm above and the yielding below. The firm occupying the upper position and the yielding dwelling in the lower position is the enduring Way.
'Thunder and wind join together': when thunder rouses, the wind rises; the two rely on each other and mutually assist their momentum, hence they are said to join together, which is their regular state.
'Gentle yielding and moving': below is Xun, representing compliance; above is Zhen, representing movement—this constitutes moving with compliance.
The creations and transformations of Heaven and Earth endure endlessly simply because they move with compliance; moving with compliance is the way of duration. How could movement without compliance ever endure?
'The firm and the yielding all correspond': all the firm and yielding lines of the hexagram correspond with each other, and mutual correspondence between firm and yielding is the constant of principle.
These four are the Way of duration, and the reason why the hexagram is Duration. Duration. The way of duration can bring success without blame, but what is endured must attain its correctness; losing correctness makes it no longer a way worth enduring.
Therefore it says, 'enduring in its way'—its way being the correct way that can endure. Not enduring in one's virtue or enduring in what is incorrect will neither bring success nor avoid blame. That Heaven and Earth never cease is because they possess an enduring Way.
If humans can endure in the way that can endure, they harmonize with the principle of Heaven and Earth. In the principle of the world, nothing can endure without moving. Movement reaches an end and begins anew, which is why it endures without exhaustion.
Among all things produced by Heaven and Earth, even the solid mass of high mountains, none can remain unchanged. Therefore, duration does not mean being fixed in one state; if fixed, it cannot endure. Only adapting to the times constitutes the constant Way.
Hence it says 'it is advantageous to have somewhere to go,' making this principle clear for fear that people might cling rigidly to constancy.
This speaks to the utmost of constant principle: the sun and moon are merely the refined qi of yin and yang; only by complying with the Way of Heaven in their comings, goings, waxings, and wanings can they shine long without ceasing, having attained Heaven and complied with heavenly principle.
The four seasons are merely the qi of yin and yang; in their cycling and transformation, generating and completing the myriad things, they also attain Heaven and therefore endure endlessly without ceasing.
The sage practices the enduring Way with constancy, and all under heaven is transformed to form good customs.
'Observing what they endure' means observing the enduring illumination of the sun and moon, the enduring completion of the four seasons, and the principle by which the sage's way can endure. Observing this, the true nature of Heaven, Earth, and all things can be seen.
The enduring Way of Heaven and Earth and the constant principles of all under heaven—who could know them except one who understands the Way?