Remembered Sandwich

One of the girls that live here was making a packed lunch for tomorrow consisting of a tuna sandwich, a banana and a pot of instant porridge (just add hot water).When she had completed her preperations she put the pot and banana in a plastic bag to take up to her room and the sandwich into the fridge. When I enquired why she hadn't put the sandwich into the bag and then the whole packed lunch into the fridge ready for tomorrow she answered by saying that if she did that then she might forget to take it but with the plastic bag in her room as a reminder of the sandwich in the fridge then she wouldn't forget. Clever stuff I thought.