Let me clarify. I did not love the article because it was in Playboy. I loved it because it was a well-written article that layed out a very clear strategy for a scientific study of the UFO phenomenon and it gave me a whole lot of material for the Hynek book.
In my favorite passage, Hynek makes the case for developing an active approach to UFO research as an alternative to the standard passive approach of investigating sightings after they occur (which, in all honesty, is what I do as a MUFON Certified UFO Field Investigator).
He starts out by stating that the passive study of UFOs "is capable of establishing the likelihood that the UFO phenomenon represents something heretofore not recognized in the present-day scientific framework," but is incapable of actually proving it.
"The passive method..." he says, "puts me in mind of the story told about the explorer who had come back from a dinosaur-egg-hunting expedition in the Gobi desert. In his lecture, the explorer presented many cogent reasons why the eggs they discovered were dinosaur eggs. He pointed out that they were about the size and weight to be expected of dinosaur eggs, allowing for dessication and the ravages of time, and that they had about the right color, given the effects of weathering -- all of this leading to strong likelihood that the eggs were, indeed, dinosaur eggs. "'And furthermore,' "the lecturer stated at the conclusion of his talk, "'when we opened one of the eggs, it had a baby dinosaur in it.'
"What is needed in the UFO problem," Dr. Hynek concluded, is a baby UFO somewhere in the crates of UFO reports.
Sad to say, 45 years later we still haven't found the baby UFO, and there are a "lot "more crates full of UFO reports now then there were when Hynek wrote this.