Final answer:
The literary term in the provided lines is an aphorism, which is a brief statement expressing a general truth or principle, distinct from an allegory, simile, or paradox.
Step-by-step explanation:
The literary term that stands out in the lines from "True ease in writing comes from Art, not chance" is an aphorism. An aphorism is a concise statement designed to convey a general truth or principle. This type of statement often embodies a quick, understandable wisdom that is easily remembered and sometimes used as a guiding principle in life or art.
In contrast to an allegory, which is a narrative with a hidden moral message, or a simile, which compares two unlike things using "like" or "as," an aphorism does not imply a comparison or a narrative but rather stands alone as an observation or principle.
Moreover, it is not a paradox, which is a statement that appears self-contradictory but in reality reveals a deeper truth. The aphorism in the given lines suggests that writing with ease and grace is the result of careful craft and learned skill, rather than mere luck or happenstance.