What is the purpose of the scene in Leo Tolstoy’s The Death of Ivan Ilyich in which Ivan Ilyich thinks about the following logical argument, known as a syllogism?

Caius is a man, men are mortal, therefore Caius is mortal." This old syllogism, learned in Logic class, flashes now before Iván Ilych with new immediacy. While he certainly felt the syllogism to be true to Caius before, accepting that it applies to himself is considerably more difficult. He remembers the emotions and the sensations of his whole life, from boyhood on, and cannot believe that a creature with such experiences must also die.