وفيه نظر؛ لأنه أفعل من الجسامة بمعنى الضخامة وعظم المقدار
This needs examination: “ajsam” is a comparative of jasāmah, meaning bulk or magnitude.
Being a body and being a larger body are different claims. Both a small body and a large one may be bodies; calling the latter “more massive” does not establish the minimum number of parts required by the definition of body.
This is a general logical caution: the comparative form of a word does not necessarily supply gradations of every technical concept related to its root. Ordinary lexical meaning and stipulated technical meaning must be separated.