In July, we rapped the Romney campaign for their failure to understand that a Venn diagram is not the same as a subtraction problem. Today, it's the Obama team's turn.

You may well be familiar with Venn diagrams – the ubiquitous pictures of typically two or three intersecting circles, illustrating the relationships between two or three collections of things. For ...

For example, during the pandemic, Venn diagrams helped to illustrate symptoms of COVID-19 that are distinct from seasonal allergies. They are also often taught to school children and are typically ...