The three-message rule: if a WhatsApp argument isn't settled in three messages, put the phone down, advises psychologist Silvia Congost

Three messages. That, according to relationship psychologist Silvia Congost, is all a WhatsApp argument is worth. "If it hasn't been resolved in three messages, put the phone down and take the conversation into the real world," she says. Her "three-message rule" sounds like magazine advice, but it hits the exact spot where a lot of relationships break: inside the small rectangle of a screen.

The explanation is simple. Face to face, Congost says, "there's a look, there's tone, expression. There's a hug." In a chat there's none of that - only words, and the brain fills in the blanks. "When we don't have complete information about something, our brain starts thinking," the psychologist explains. And thinking at midnight over an unanswered message rarely ends in a positive conclusion.

That's why a late reply doesn't necessarily mean lack of interest. Psychologist José Martín del Pliego points out that we all live under a flood of alerts: "There are too many stimuli, too many notifications, and that creates a burden." A partner who hasn't replied in twenty minutes may simply not have been able to read one more message. It doesn't have to mean they're punishing you.

Clinical psychologist Pilar Guerra goes a step further. For her, "communication is the most powerful weapon a human being has", but only if it's honest. She calls it "honest self-expression" - speaking from your own emotion instead of throwing out reproaches. "I feel ignored" opens a conversation. "You never answer" shuts it down.

What the rule doesn't say matters too. Putting down the phone doesn't mean dropping the problem, or using silence as punishment. The advice is to agree on when you'll talk, and to respect the time the other person needs.

The generations before us settled arguments at the kitchen table or on the bench outside the apartment block. We fight them with our thumbs, with a "..." that appears and disappears. How many relationships would survive simply because someone put the phone down in time?