He says:

“Abū al-Husayn al-Basrī said: ‘Speakers of the language apply the term qur’ to both menstruation and purity, which are opposites. This demonstrates that homonymous expressions occur in the language.’”

He says:

“One may object: Those who originally assigned the term have not been reported as declaring it homonymous. All that is established is that a single term has multiple referents. Perhaps it was applied to both on account of a single meaning common to them, rather than their differing realities. Alternatively, it may be literal in one case and figurative in the other, even though we do not know which usage is literal and which is figurative. These explanations are preferable: the first avoids both figurative usage and homonymy, while the second rests on the principle that figurative usage is preferable to homonymy, as will be explained in its proper place.”

He says:

“A stronger argument is the universal agreement that the term ‘existence’ applies literally to both the eternal and the temporally originated. Were its application figurative in either case, it could validly be denied, since this is a sign of figurative usage; yet such denial is impossible. Accordingly, the term ‘existence’ must denote either the Lord’s essence or a reality additional to His essence.

“If the former, it is evident that the Lord’s essence is intrinsically different from all other, temporally originated beings. Otherwise, it and whatever shared its meaning would necessarily share necessary existence, since they would be equal in what is meant by ‘essence’; but this is impossible. If, however, the term ‘existence’ denotes an attribute additional to the essence of the Lord—exalted is He—