I know it's summer and too humid to think, but indulge me, if you will, in a flash quiz on flash mobs.

8 teens beat man to death for 6 beers

George Bird, 59, described by a neighbor as a "worthy man," was set upon by eight teenagers who battered him to the sidewalk and kicked him to death before fleeing with the six-pack of beer he had been carrying.

 The above headline and story ran when in the Daily News?

(A) 2011

(B) 1991

(C) 1981

Urban nightmare

Mr. Smith, 25, was walking toward a bus stop on his way home from work last Monday night when he was surrounded and assaulted by members of a group of about 10 teenagers, three of them carrying knives. Many had just been kicked out of the Superarcade amusement center on Chestnut Street near 16th.

 Same question, only when did this appear in The Inquirer?

(A) 2009

(B) 1999

(C) 1989

What's behind "flash mobs"?

John Rich, a physician and an expert on urban violence at the Drexel University School of Public Health, said it would be foolish to ascribe racist tendencies to the youths who did violence when unformed teenage brains might be more to blame.

"This is the way adolescents are," Rich said. "Doing unwise, risky things is what adolescents do."

 Rich's assessment was published when?

(A) Last month

(B) Last week

(C) Last year

If you answered C to each question, congratulations! You, too, know that Philadelphia teenagers have been terrorizing adults since long before they could organize anarchy with smartphones.

And yet, this summer's flash mobs make news even if neither the motivation nor response is new.

In 1980, an idealistic Wharton urban planning student died after being beaten by kids whose lives he aimed to brighten. Then, and now, advocates and academics blamed poverty, fractured families, and lack of structured activities.

In 1998, then-City Councilman Michael Nutter unleashed a screed after Greek Picnic-related mayhem.

"What would we be saying if males from the Ku Klux Klan or the Aryan Nations attacked, stripped, assaulted and violated black women?" Nutter wrote in an op-ed to a strangely silent black community.

"It's not about what the white man did," he elaborated in an interview at the time. "It's not about slavery or oppression. It's about nothing. It's about being ignorant and disrespectful."

Nutter said as much from the pulpit and podium this week, though my colleague Annette John-Hall wisely noted he seemed to be performing just as much for white voters and scared suburbanites.

The mayor also decried the loss of 5,000 summer jobs due to federal budget cuts. If I didn't know better, I'd have thought he was suggesting that Congress sent the texts that spawned recent flash mobs.

Pity the fools

The 1980s-era random acts of violence were committed by thugs that cops dubbed "wolf packs" looking to "get a beat" on weaklings.

In the 1990s, "whirling" and "wilding" were used to describe the senselessness. (The latter, Penn professor of linguistics Mark Liberman tells me, likely arose from a "misunderstanding of wild thing.")

More recently, adults confused "catchin' rep" and "catch and wreck," both of which quickly gave way to flash mob - a term itself ruthlessly stolen from fun-seeking impromptu opera singers.

Don't fret if you haven't figured out the lingo. And don't stay home, either. Center City is crawling with cops for the foreseeable future. Nutter made sure of that.

Today's flash mob fear and venom will soon subside, returning at a later date with a new name, increased outrage, and the same institutional inability to stop history from savagely repeating itself.

Contact Monica Yant Kinney at 215-854-4670, myant@phillynews.com or @myantkinney on Twitter. Read her blog at philly.com/blinq.