The bottle at the next table

Late one evening, in a kushari shop off the pyramids road in Giza, two visitors sit down at the next table and reach for the small bottles in the middle.

One holds garlic vinegar. The other holds the chilli sauce, and they are about to pour it with the same generous hand.

Half the room can see what is coming. A few people grin and nudge each other. That is the easy option, and there is nothing brave in it. Watching strangers walk into a small disaster and enjoying it with your friends takes no nerve at all.

The harder thing is to lean across and say, gently, go slowly with that one.

It feels risky. You are a stranger. You might sound as if you think they are foolish. They might not understand you, or might wave you off, and the whole shop will see it happen.

In practice, almost nothing can go wrong. The worst outcome is a polite nod and a mouthful of fire anyway.

What makes the moment brave is not the size of the danger. It is that the act is for somebody else. A risk taken purely to protect your own pride is a different thing, closer to stubbornness than to courage. The person who leans over is spending a little of their own comfort so that two strangers do not ruin their dinner.

Most of us measure these moments the wrong way round. We spend our attention on how frightening it feels, and almost none on how useful it would be to the people in front of us.

Count the usefulness first. It turns out to be stronger than the nerves.