both of these sketches are by M.C Escher. most of his drawings are very trippy and make your eyes wander from object to object, and they make you question what you're actually looking at. The first picture consists of multiple stairways that lead to multiple places. You can flip this picture any way you would like and you would get a different perspective of it. The second drawing is a man holding a mirrored ball. The view that you see is the man who is holding it, and hes looking into it. This picture as well is confusing and makes you wonder why he is looking into it. The background is detailed, showing the entire room that he is in and the chair that he is sitting in.