The public have always enjoyed fear. I think it all starts when the child is three months old. The tiny baby is in its mother's arms and the mother says, "Boo". It gives the poor child the hiccups, but eventually the child recovers from the shock and smiles, so the mother smiles too. That's the first taste of fear ever given to a child.
Later on it gets on a swing, swings higher and higher and nearly goes over the top. Then it eventually pays money to go on things like the scenic railway, switchback, Big Dipper or whatever they call the thing nowadays. Everyone screams as it goes down the first big dip. Then they pay money to go in things like the Haunted House, the Ghost Train, the Horror Caves and give themselves a fright. Now why do people want to pay money to be scared? I don't know it's a strange phenomenon.
Audiences are really strange. They love to dip their toe into this cold water of fear, and you know people have said things that are horrific on the screen are a bad influence. They're not, really. They might possibly be a bad influence on sick minds, but not on those with healthy minds who like to enjoy a little scare.
I'm often referred to as a maker of mystery thrillers. This isn't true. I never make mystery films for a very simple reason. A mystery is something that the public are trying to discover and it's an intellectual process. I've only made one who-dun-it. It was a film called 'Murder'. Herbert Marshall was the leading man and that was really a who-dun-it in terms of looking and searching ... seeking out a murderer. There's no emotion in a who-dun-it because you withhold information from an audience. The element of suspense is giving them information.
You and I are sitting here . . . . suddenly a bomb goes off and up we go, blown to smithereens. What have the audience had while watching this scene? Five or ten seconds of shock. Now we do the scene over again, it's a five minute scene. You and I are talking about football, something very innocuous, but the audience are informed by a method unknown to us that there's a bomb under the table and it's going to go off in five minutes.
Now this innocuous conversation about football becomes very potent. "Don't talk about football, there's a bomb under there", that's what they want to tell us, as the bomb ticks away aand we keep telling the audience there's a minute to go; half a minute and finally ten seconds. That is when it must not go off. If we let it go off, the audience will be as mad as hell with us, they'll be disgusted. They'll say, "Don't go and see that movie or that play".
Your toe MUST touch the bomb at the last minute, you must look under the table, grab the bomb and throw it out of the window, then it can go off; but you and I must be saved. An audience needs that relief after you've put them through the ringer.

This article by Alfred Hitchcock appeared in the book, 'Heard in the Wings' which was edited by Roderick Bloomfield and published by Stanley Paul in 1971. It was one of a series of books on humour. The illustration is by Bill Tidy and comes from the same book.