Final answer:
In the context of the allegory of the cave, the darkness represents ignorance and therefore does not understand 'the light,' which symbolizes knowledge and truth.
Step-by-step explanation:
The phrase “the darkness does not understand” can be interpreted from the Socratic and philosophical perspectives, especially given its reference to knowledge and the allegory of the cave.
In the context provided, it is clear that the darkness symbolizes the ignorance and the inability to comprehend truth and knowledge.
Therefore, what “the darkness does not understand” in its most direct interpretation from the allegory is the light, representative of knowledge and truth.