Answer: Its called an illusion. They practice the trick several times to perfect it to where people think it is magic.
Explanation:
Everyone stop what you are doing the cat is napping
Depending on where you are brought up, and the difference in society, you will see different things and people will have different beliefs in symbolism. For example, seeing a bird in a picture for a Christian may represent a dove and be seen as peace, but for someone else it may be seen as a vulture and represent death
There are many artistic tasks that the monks and nuns performed at the time. Here are some of such options:
1. painters - given that they had some free time, monks and nuns resorted to painting to kill time
2. weavers - nuns would usually weave or embroider in order to create beautiful patterns of cloths
3. carvers - especially monks did this - carving wooden objects was a good way to both train and entertain themselves