Why had the actor chosen so public a platform to reveal his sentiments? Was it a publicity stunt to promote his new film War of the Worlds? Or yet another example of the trend for celebrities to reveal all on the public stage?

Perhaps Cruise’s actions confront us with a more philosophical dilemma. Psychologists — from the 19th-century American William James onwards — have studied the expression of emotions. The problem, in a nutshell, is this: is an emotion different from the expression of an emotion? If we display the facial signs of, say, joy or anger, is this the same thing as actual joy or anger?

It might seem obvious that emotions can be faked, but this gets complicated when we realise that what we know about emotions mainly involves external signs. What we call emotions are so bound up with their expression that it is not so easy to distinguish the two.

In one study, people were forced to wear a mechanical apparatus that fixed their expression into a smile or a frown. They were then shown cartoons. Those made to smile claimed to find the films funnier, while the frowners were less amused. It was as if the outward manifestation of emotion was actually creating or intensifying it.

This suggests that faking a feeling can make it real. In Hitchcock’s film Notorious, Cary Grant and Ingrid Bergman pretend to be lovers when caught searching a wine cellar by Nazi spies. Yet sure enough this love becomes real. And actors and actresses playing lovers on screen frequently end up as a genuine item. The external becomes the internal.

This is the principle of a show such as Celebrity Love Island. The characters are expected to develop feelings for each other which makes them more likely to have the feelings. We watch as emotions are manufactured before our eyes.

But why does all this need to be done in public? Perhaps it suggests that emotions need an audience to become truly real. This is especially so if we are unsure as to what we feel. A public declaration can turn this doubt into conviction however transitory.

This might explain why a marriage ceremony requires witnesses. When a couple declare their feelings for each other, a third party must be present to act as a sort of emotional guarantor. The words have to be made real.

And perhaps this was the role of Oprah for Tom Cruise.

Darian Leader is a psychoanalyst and author

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