My go-to A Christmas Carol movie is the 1938 MGM version starring Reginald Owen as Ebenezer Scrooge. I’ve watched it season after season for decades.
And after all these years (with the help of Brewer & Shipley) I’ve finally concluded that the reason Scrooge saw spirits were spirits.
Early in the movie, Fred Scrooge, Ebenezer’s nephew, arrives at his uncle’s cold, dismal counting house and greets clerk Bob Cratchit with a big, warm, friendly smile.
Fred Scrooge: [Presenting a bottle]
This’ll make the place less bleak.
Bob Cratchit:
What might that be?
Fred:
It’s a wine bottle. A cheering, warming, goodly wine. A wine that’ll race through your veins with little torches. Its port, Bob—the fifth essence of the Christmas spirit. [Fred looks around] But we haven’t got a glass.
Bob:
I’ll get one from Mr. Scrooge’s office.
Fred: [He wipes out his uncle’s filthy glass and smells it]
What is this?
Bob:
His cough medicine.
Later that night, Ebenezer, closing the counting house, sees the bottle of fortified wine on Cratchit’s desk—still mostly full. He starts to throw it in a trash bin, but smelling the contents, he puts the bottle in a back pocket under his long winter coat and heads home.
Standing before the fireplace in his bed chamber, Scrooge pulls a medicine bottle and spoon from the mantle and takes a generous dose. It appears to be a ritual.
For the first time while watching Ebenezer’s interaction with the spirits—the ghostly ones—I thought of a song, and it brought forth an epiphany—I’ve paraphrased the lyrics here:

I’m pretty sure I’m on to something. For reference, here’s the song from B&S:
Skeptical? In Dickens’ time, cough medicine was available to anyone who could afford a bottle, and common ingredients included opium, morphine, cannabis, alcohol, and chloroform. Draw your own conclusions. Here’s an actual label from an 1800s cough medicine bottle:

Merry Christmas to you and yours. Have some Port wine, and let me know if you see spirits!

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