西周官制的研究中，過去以冊命銘文為主，而後李峰關注西周貴族的仕途發展，並提出「副職」一說，論述頗豐。此觀點主要著眼於西周中期銅器銘文中出現的「疋」某人的例子，認為這些職位是試用性、一時性的，最終將升為正職。然細察其例證，或有可能是同名異人，不宜貿然判斷兩器銘文所載為同一人的仕途。故本文重新探討「副職說」的例證，並試對西周金文所呈現的貴族仕途呈現的諸多現象提出職官擴張與壽短、致仕等解釋

In the past, the research of the bureaucracy in Western Zhou was focused on Appointment Inscriptions. Then Li Feng was interested in the career development of the aristocracy, brought up a new concept: Assissantship. The idea is based on ＂pi＂（疋）, a character recorded on multiple bronze inscriptions of mid-Western Zhou. Li Feng assumed that the positions of assistance were probationary and temporary. Finally it can be transferred to permanent employment. Futhermore, according to survey the evidences, these could be the people that have the same name but different people. Thus people can not consider these evidences as the career of development of the same people. Therefore, the main goal of this thesis study is to review the evidence for the hypothesis of ＂assistant＂. Furthermore, the aristocracy of the career development presenation were recorded on the bronze inscriptions including official expansion, short life span and retirement which will be submitted an explanation