"Just how do you mean that, sir?" was Benjamin Braddock's response to Mr. McGuire's career advice in "The Graduate."

Mr. McGuire had it right in 1967: Plastic may be the 20th century's most lasting legacy.

Today is the 75th anniversary of the "invention" of plastic. It seems to be passing without notice, except for this story from the Independent in London.

That's unfortunate. Scientists had worked on the idea of plastic for centuries. As with many inventions, several take credit and/or blame for a product that, by one tally, accounts for 1 million plastic bags used around the world every minute.

Paternity could go to American Charles Goodyear and the invention of vulcanized rubber in 1839, or Alexander Parkes, an Englishman, who mixed a form of plant matter with alcohol and camphor to make a hard-but-flexible material he called "Parksine" in 1855. Some would label Bakelite (1909, Belgian-American Leo Baekeland) the father of it all. Bakelite was the first plastic to hold its shape after being heated.

Forgotten until 1933
The Independent points to a German, Hans von Pechmann, who accidentally made polythene (later called polyethylene) in 1899 and promptly set it aside to be forgotten until 1933.

That year, two Englishmen, Reginald Gibson and Eric Fawcett, were messing around with various gases under pressure. One result was found in Gibson's understated lab note: "waxy solid found in reaction tube." He and Fawcett eventually came up with a low-density polyethylene and a high-density polyethylene. The low-density stuff (#4 on your recycling label, which is called a "resin identification code") is what you find in packaging materials, for example, and the high-density polyethylene (#2 on the label) is your plastic bathroom pipe.

Seventy-five years later, use is high but the popularity of plastic is at an all-time low. Communities like San Francisco have a partial ban on plastic bags (since last November). The Chinese government is taking similar action, effective June 1.

The list of sins committed by plastic in manufacture, use and disposal is long. Its benefits, if only in food safety and handling, are usually overlooked.

I guess there won't be a birthday party today.