Chesterton re-uses the line.

“I’m rather sorry you take this so lightly,” said Fanshaw to the host; “for the truth is, I’ve brought these friends of mine with the idea of their helping you, as they know a good deal of these things. Don’t you really believe in the family story at all?”

“I don’t believe in anything,” answered Pendragon very briskly, with a bright eye cocked at a red tropical bird. “I’m a man of science.”

The Perishing of the Pendragons, G.K. Chesterton

The media (3)

‘Do you believe in curses?’ asked Smaill curiously.

‘I don’t believe in anything; I’m a journalist,’ answered the melancholy being — ‘Boon, of the Daily Wire. ...'

G.K. Chesterton, The Curse of the Golden Cross

The media (2)

Here's the original of the newspaper motto "comfort the afflicted and afflict the comfortable." Note how taking it out of context has changed the meaning.

Whin annything was wrote about a man 'twas put this way: "We undhershtand on good authority that M-l-chi H---y, Esquire, is on thrile before Judge G---n on an accusation iv l--c-ny. But we don't think it's true."... Th' newspaper does ivrything f'r us. It runs th' polis foorce an' th' banks, commands th' milishy, controls th' ligislachure, baptizes th' young, marries th' foolish, comforts th' afflicted, afflicts th' comfortable, buries th' dead an' roasts thim aftherward. They ain't annything it don't turn its hand to fr'm explainin' th' docthrine iv thransubstantiation to composin' saleratus biskit.

Newspaper Publicity in Observations by Mr. Dooley by Finley Peter Dunne (1902)