لِأَنَّ الْجَهْلَ بِالْبَعْضِ وَالْعَجْزَ عَنِ الْبَعْضِ، نَقْصٌ وَافْتِقَارٌ إِلَى مُخَصِّصٍ
Ignorance of some things and inability concerning some things entail deficiency and dependence on a determiner.
A human knows some events and not others, and can lift some weights but not heavier ones. Such limits indicate a constrained capacity. A Necessary Existent, by contrast, cannot depend on an external specification.
The reasoning does not measure divine knowledge in human quantities; it denies creaturely limitations of knowing and acting.