Cecil Moore wrote:
John Smith wrote:
While I cannot dismiss the existence of the photons, I am not aware of
any experiments which have been able to measure them.

Hecht says: "... researchers ... have conducted experiments
in which they literally counted individual photons".

Hecht is quite correct. This is a standard technique in several areas of
physics research. I personally spent several years in my relative youth
designing, building, and using photon counting apparatus.

73,
Gene
W4SZ