This paper engages the three foci of the present panel, Periodization, Diversity, and Inventiveness, to investigate the changes in poetics and aesthetics in Classical Arabic poetry, particularly in the late 4th/10th and 5th/11th century. It will attempt to argue that these changes shape out the transition from Classical to Postclassical poetry in the Arabic tradition. In terms of Periodization, while arguing, together with the well-established revisionist movement, that the 5th/11th through 12th/18th centuries cannot be dismissed, as was generally accepted in literary historical circles until the late 20th century, as an “age of decline”, this paper eschews the term “Premodern” to argue that what might better be termed the “Postclassical” period grounded its aesthetics on the recognition of the Jahili through Late Abbasid poets as the “classical” foundation, with which they saw themselves as competing as they strove to produce their own original poetry. Far from seeing themselves as mere epigones of the Masters of the Classical periods, the Postclassical poets introduced into their poetry new forms, themes, and rhetorical expectations, and celebrated their own inventiveness and originality. By their own aesthetic metrics, they even boasted that they could outdo the Classical Masters. This paper will focus on examples such as the Hijaziyyat of al-Sharif al-Radi, The Luzumiyyat of al-Ma’arri, and the Madih Nabawi (al-Shuqratisiyyah) of al-Shuqratisi, to demonstrate the evolution of poetic aesthetics in form, theme, and rhetoric in this transitional period.