Modern science achieved objectivity by removing subjectivity from theory.

Observers were treated as coordinate systems, and physical reality was assumed to exist independently of them.

This worked well for classical physics.

But quantum mechanics introduced a strange situation: measurement determines physical outcomes, yet the observing subject itself is never defined within the theory.

The observer is necessary, but structurally absent.

This raises a deeper question.

Modern knowledge is built on the subject–object distinction. But if the observing subject is excluded from theory, can a theory of observation actually be complete?

Maybe the “observer problem” in physics is not just a technical issue, but a structural consequence of removing subjectivity from the foundations of knowledge.