at the dentist’s office

i was at the dentist’s office for a follow up (from this incident) and as i was leaving, i was like “thanks dentist wilson.” huh? in the back of my mind i meant to say, “thanks dr. wilson.” it was awkward. for future reference, here is a list of occupations which get to have a specific honorific (note: list is not exhaustive):

• professor
• officer (sargent, lieutnent, detective, etc.)
• chef
• doctor
• judge (justice, comptroller, etc.)
• senator (governor, congressman, president, queen, etc.)

why do these occupations get special treatment? in the future, i will only acknowledge addresses of: dilettante ganan.