Explain · analogy · Like I'm five version
Are aliens real in terms of a lost property office
Are aliens real, or are they just items waiting in the big lost property office at the end of the universe?
The universe is like a giant school with millions of cupboards and shelves for everything that gets misplaced. When a star or a planet goes missing, or perhaps a tiny green visitor from another world wanders off, they end up in the big lost property office. Just like when you leave your favourite woolly hat on the bus, the space staff put them in a box with a little label. They stay there on a dusty shelf until someone comes to claim them, but nobody has knocked on the door yet to ask for their lost space people back.
The people who work in this office are very quiet and always keep the place tidy. They sort everything by size and colour, so there is a section for shiny spaceships, one for wiggly aliens, and a very big box for forgotten asteroids. If a planet loses its way, the office workers write a note to say it is safe. They wait for a long time in their big, cold room, hoping that a friendly traveller will come by to pick up all the bits and pieces that have been left behind.
It is a bit like looking for a lost toy, but on a much bigger scale. You have to peek behind the curtains of the stars to see if anything is hiding there. Most people have not seen an alien, so we keep waiting at the window. We are just like you checking the school office for a lunchbox, hoping that one day the door will open and someone will say that they have found what we are looking for.
Where the analogy breaks downLost property offices exist in specific buildings, whereas the universe does not have a single front desk where all missing things are gathered.