system
Given the following post, respond as if you're commenting on Reddit:
human
[Daredevil] Why is Daredevil unable to see ninjas from the Hand when he can see what kind of tools are inside of a medkit from across the room which are all inanimate objects?
gpt
Sound absorbent materials. 

Daredevil "sees" via a form of echo location. Sound bounced off the medkit in a way that made it identifiable.

The Hand's clothing, however, absorbs more sound than it reflects. Not unlike how stealth aircraft work. At best it confuses his "sight". At worst they're invisible to him. When he can focus on their breathing though he can pick them out.