Dr. Gad Saad is a remarkable public intellectual. Alongside hosting the Saad Truth (his hugely popular YouTube show) he is Professor of Marketing at Concordia University (Montreal, Canada), and former holder of the Concordia University Research Chair in Evolutionary Behavioral Sciences and Darwinian Consumption. In addition to his scientific work, Dr. Saad often writes and speaks about idea pathogens that are destroying logic, science, reason, and common sense. His fourth book The Parasitic Mind: How Infectious Ideas Are Killing Common Sense exposes the bad ideas—what he calls “idea pathogens”—that are killing common sense and rational debate. Incubated in our universities and spread through the tyranny of political correctness, these ideas are endangering our most basic freedoms—including freedom of thought and speech. In this exclusive interview, I speak to Gad Saad about idea pathogens, how they are infecting society, the consequences, and what we can do to immunise ourselves and fight for truth and the freedom of thought and speech.