You argument really depends on what you mean by "Prove".
Per dictionary.com :
to establish the truth or genuineness of, as by evidence or argument: to prove one's claim.
Law. to establish the authenticity or validity of (a will); probate.
to give demonstration of by action.
to subject to a test, experiment, comparison, analysis, or the like, to determine quality, amount, acceptability, characteristics, etc.: to prove ore.
to show (oneself) to have the character or ability expected of one, especially through one's actions.
I think it is reasonable to say that I can "prove" the photons originated from my light bulb.