This is from the great Pictures on a Page, by Harold Evans. Originally published in Esquire in 1974.
But is it really life size? On the printed page, yes it is. On the web, who knows? It all depends on how your device scales it. That’s something that goes missing in the digital world. For the record, “life size” in this case is 173 mm wide from the left margin of the picture to the right. If you want to compare your fist to Ali’s—and yes, it really is kind of irresistible—zoom in and out until that’s how big the image is.