>>>Whether of not a murderer's hair strand is discovered at the scene of a
crime, and regardless of whether the constabulary (who perhaps have a bald
man as their main suspect) search for it, it IS evidence. It is possible or
potential, rather than actual, evidence, and occupies the same ontological
status nor permits of the same phenomenological distinctions as, say,
photons of a certain spectrum, which are constituted as color only if
perceived.<<<
No, it is not evidence. It is a physical fact. "Evidence" is the interaction of physical facts with the desire to prove something. (Again, the analogy to sound.)
Without that desire the hair is not evidence. It is hair, and nothing more.
-Prof. Tim