Artists Jennifer Allora and Guillermo Calzadilla often begin a project by asking the question, "What are the meanings connoted by the use of certain materials?" For them, chalk is both an “ideological tool,” as something used in a classroom, and a geological substance found in the earth. Because of the nature of chalk, the artists decided to create a chalk sculpture in a public square. In this video segment from Art in the 21st Century: Paradox, see what happened when people in Peru were given the opportunity to write or create images with giant pieces of chalk in a public place and how this event addressed the topic of freedom of speech.