This short essay takes as its starting point the book “The Voyage on the North Sea”. Art in the Age of the Post-Medium Condition (1999), written by the American art critic and art theorist Rosalind Krauss (1941). Here we recognize the importance of her book to analyze the concept of the “medium” and the emergence of the “post-medium” paradigm. We will also embrace Krauss’s notion of “differential specificity” to think about contemporary art practices. The work of William Kentridge will helps us to deepen the stated assumptions. We will analyze with particular consideration his recurrence to a specific technique of animation which is endowed with a characteristic obsolescence.