Maurits Cornelis Escher, a Dutch artist, is well-known world-wide for his interesting and sometimes puzzling graphic works. His Waterfall and Ascending and Descending are the artistic implementations of Penrose’s idea of an impossible object. That is why the observer needs to examine the geometry of the work carefully in order to understand where the misleading point is and why the stairs on the roof will never end and the process of ascending and descending will never stop. All the main elements of the work are chosen due to the main idea, most of the shapes are math like, forms are geometric and small, while the lines are straight and diagonal. The observer can not find a single vertical or horizontal line in the work. Ascending and Descending was used by mathematicians in their works and inspired them for further researches, the work is said to be based on a strong scientific basis. But Maurits has never regarded himself a mathematician. At school I never received a good mark in mathematics… And now mathematicians use my pictures in their books. They greet me as a lost brother who has been newly found! They don”t suspect that in mathematics I am absolutely illiterate (Ushakov, 316). Escher uses contrasting darker and lighter colours only to accentuate the straightness of the lines and the acute angles. Another question is dull and neutral tones of the picture, which are determined by the place and the situation. The monks, identically dressed, obediently ascending and descending the stairs could not be depicted in other but grey and neutral colours. Extreme repetition of elements – numerous identical monks, small windows and the steps of the staircase – creates the feeling of rhythm. In fact, during this useless ritual of ascending and descending, there could be beaten some rhythm, so the observer gets the feeling of personal presence while the visual and auditory perception become united. The center of interest is the never-ending staircase on the roof, it puzzles the observer most. One needs several seconds to understand what makes the impression that the stairs will never end, at what point the author did not keep to the normal size proportions, where the impossible object is hidden. To see how much he has tricked you, notice that the staircase makes four right- angle turns going around the courtyard, indicating that the courtyard should be rectangular; however, the upper-left-hand side of the courtyard is much shorter than the lower-right-hand side. Escher’s courtyard does not obey the laws of Euclidean geometry, which state that that opposite sides of a rectangle should be equal in length (Gott, 104). It makes the observer be active and find the contradiction in the picture, paying attention to the slightest detail. Another interesting point is the two individuals, which refused to participate in the exercise, though not ruining the harmony, as one of them is looking at the moving monks, another one sitting seems to be bored, so they will soon join the other. I admired the idea of never-ending staircase in the picture as it proves how relative the human perception is. I liked the feeling of rhythm involving in the situation observed. But I would rather spoil the over-all harmony of