Chapter 8 of the Suwen: The Small Intestine

小 腸 者 ， 受 盛 之 官 ， 化 物 出 焉 。

The Small Intestine holds the office of Receiver and Repository, the transfer of matter comes from it.

The office of receiving and containing can be used as a metaphor for the job that the Small Intestine plays in the body. I see this role as being the officer in charge of buying and storing for the household, or palace. The Small Intestine goes to town, and in following the mandate of the Empress, the Small Intestine receives the items that are necessary for the proper functioning of the household. The SI contains these items for a long enough duration to bring them into the palace, and once there, transforms each and everyone of them into something that can be stored in the offices that are held by the Zang organs, and particularly by the office of the Heart.
Once we get to the Kidney, it is said that the Kidney holds the office of 作強, or “making strong.” It is only with the building blocks provided and transformed by the Small Intestine that the Kidney can use it’s abilities to fortify the body. This can be traced back to the Heart again.
As empress, the Heart holds the ideas. In order to birth these into the material world, the substances for that birth must be gathered. They must be transformed, in that the pure and useable essences are separated from the impure and unusable essences. The Small Intestine does all of this. In the same way that we think about the anatomical small intestine, we can think about the Chinese Small Intestine and it’s ability to do this with everything we are digesting, including thoughts. This separation through transformation can be reflected psychologically as well as physiologically.