Which ancient Greek philosopher is said to have lived in a barrel?

Diogenes of Sinope was an ancient Greek philosopher and self-proclaimed "Citizen of the World" who, at different points, allegedly lived in a wine barrel (or possibly another kind of jar), urinated on guests at a banquet, and made a regular practice of insulting famous figures and lecturing shoppers in the marketplace. Plato reportedly called him “a Socrates gone mad,” while 21st century historians have compared his life to “one long Monty Python sketch.” But, though some believed him to be crazy, Diogenes was also one of the most respected and beloved philosophers of the 4th century BCE, and one of the founders of the ancient Greek school of philosophy known as Cynicism.

It’s important to note, from the outset, that there is a huge amount of historical speculation about Diogenes: The philosopher left behind no first-hand accounts of his own life (or if he did, they’ve since been lost), and his larger-than-life persona has likely inspired plenty of apocryphal tales over the last 2500 or so years. Nevertheless, the legend and legacy of Diogenes, as much as the actual person, have played an essential role in the evolution of philosophy as a discipline.