枚乘〈七發〉向來被認為是古代七之文類的首倡之作，在東漢之後，引起許多仿作，遂而使「七」形成一種文類。而這些作品因為大量呈現耳目聲色娛樂，最後才進以正道妙理，所以常引來「勸百諷一」的負面批評；但這種奢華的享樂，其實是一合於漢人禮教思想的說服策略。在此遊樂的過程中，又包呈顯出漢代天人合一的思想，有著特殊的文化意涵。東漢之後，眾七之作不約而同出現了儒、道二家思想的抗辯，與原來〈七發〉大不相同，其實，這也與東漢之後隱士抗旨不奉朝聘的風氣密切相關。 從文類發展的角度來說，七其實是在漢賦之下發展起來的，故七經常被以漢賦的評價標準衡量之，但七與漢賦終究不同之處何在？除了對問凡七、主客雙方始異終契、論說義理之外，主要更在於「求賢招隱」此一題材與目的上；此題材與目的為傳統漢賦所無，傅毅〈七激〉問世，便為此確立典範，引起許多仿作，篇章既多，遂而成類。漢迄於六朝，七的體貌大同小異，直到唐代之後，才突破窠臼，使該文類有了新的發展。

Qi-Fa is considered the first composition of Qi genre, during East Han Qi was created generally so be a literature genre. This kind of articles was filled with many kinds desires so get bad command. In the fact, this phenomenon revealed the moral conception and university-human relationship. Beside, the development of Qi was considered to be subordinated to Han-fu, whereas the different between Han-fu and Qi, the major point is 「recruiting recluses」, After Fu-Chan's Qi-gj, many articles simulated it, and Qi be a literature genre, until Taun-Dynasty, Qi had broken it's original type.