The equation appeared on Malcolm Jenkins' face as he stood on a patch of carpet and glanced toward the back wall. It was not written, but it was there, his muscles crackling with the calculus spinning in his brain: a curl in the upper lip, a dip in the arches above his brow, an expression that simultaneously combined irony, amusement, and a sprinkling of pride.

"We don't have anything," the Eagles safety said. "We're at the bottom just like everybody else."

That was one side of the equation. The other one was at the opposite end of his gaze, a picture of a silver trophy that challenged the validity of the words he'd just spoken. The words accompanying the image erased any question about its significance.

Super Bowl LII Champions. 

"I hate it, personally," Jenkins said. "My focus is all on adding another 'I' to the end of that. And so it's great. But I'm well beyond celebrating last year's accomplishments, because they don't mean anything this year. They don't get us anything."

I hate it. It's great. But it doesn't mean anything.

Thursday night marks the dawn of a new era in Eagles football, the opening round of the first Super Bowl defense in franchise history. With it, the animating question shifts from "Can they?" to "How long?" 

There are a lot of concrete variables that will determine the number of Roman numerals that materialize on the NovaCare Complex walls between now and the arrival of the next extended stretch of desolation. Uniting them all is the psychological push-pull reflected in Jenkins' musings. 

There is meaning in accomplishment. But there is no accomplishment in that meaning. 

•••

Buddy Ryan is carried off the field by his Chicago Bears after they beat the Patriots in Super Bowl XX.
AP FILE
Buddy Ryan is carried off the field by his Chicago Bears after they beat the Patriots in Super Bowl XX.

The history of Super Bowl champion is written in three different increments. There are chapters, there are acts, and there are full-blown epics, the latter complete with beginning, middle, and end. Such is the appropriate framework to use when considering how the Eagles' story might ultimately be written. 

The chapters belong to the anomalies, the one-hit wonders, the 2002 Bucs, the 2000 Ravens, the '85 Bears. Such a characterization does not imply that their success was limited to that championship season. But, for our purposes, success is merely a baseline.

Of the 35 champions between 1978 and 2012, 19 averaged at least 10 wins per season over the next five years. Of the 15 organizations that won titles during that stretch, eight won at least two of them in a five-year span. Of the seven that did not, four had a quarterback who could reasonably be considered a franchise-type, and all advanced to at least one other Super Bowl with their man at the helm: the Rams (Kurt Warner), the Colts (Peyton Manning), the Packers (Brett Favre), and the Saints (Drew Brees). 

The remainder feature a host of journeymen and middle-of-the-packers (the Bears' Jim McMahon, the Bucs' Brad Johnson, the Ravens' Trent Dilfer and Joe Flacco). We have seen enough of Carson Wentz to confidently say that, assuming good health, he belongs in the former category. 

It goes without saying that the quarterback position is the most glaring commonality amongst those whose Super Bowl success exceeded a single season (albeit, with an acknowledgement of the chicken-and-egg component that is unavoidable in such an observation). 

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In Wentz, we have the single greatest reason to believe that the next five to 10 regular seasons will unfold in a manner similar to one in which 2017 did. As long as No. 11 is healthy, the Eagles will be in the Super Bowl conversation more seasons than not. They are not an outlier. Not close. And that is that. 

The more interesting lines of demarcation are the ones that stretch between the perennial contenders and the multiple winners, and between the multiple winners and the full-fledged dynasties. 

Dividing the past into such buckets is a difficult enough task. If we consider dynasties to be singular in nature, it is difficult to count more than four over the last 40-plus years.

We start with the Steelers from 1974 through 1979: four Super Bowl titles and a regular-season record of 67-20-1. We proceed to the 49ers from 1981 to 1992: four Super Bowl titles and three other conference championship appearances in 12 seasons. Next come the Cowboys from 1992 to 1995: a relatively brief reign but one that featured four straight conference championship games and three titles.

After a brief interlude, the Patriots began their current run that features eight Super Bowl appearances, five titles, and four other conference championship games, a run of dominance that stretches from 2001 to the present day. 

The rest of the lot are a mix of perennial contenders (the Colts with Manning, the Broncos with John Elway, the Packers with Aaron Rodgers, the Steelers with Ben Roethlisberger) and difficult-to-define cases (the Giants with Eli Manning, the Saints with Drew Brees and Sean Payton). 

In setting a benchmark for the Eagles, it makes most sense to focus not on the dynasties, for the strengths that separate them are in large part the failings that relegate the rest to lower ground. 

Beyond the quarterback, the single greatest commonality uniting our four dynasties is situated in the offensive line. During the 49ers' reign from 1981 through 1994, eight players combined to start 797 of a potential 1,080 games at the five spots along the offensive line. That run featured two different core groups, with four of five starters intact between 1981 and 1986 and three of five unchanged between 1987 and 1994. 

In Pittsburgh, the story was the same, with tackle Jon Kolb and guards Gerry Mullins and Sam Davis each starting at least 79 of the 88 regular-season games of the Steelers dynasty that stretched from 1974 through 1979. 

From 1992 to 1995, the Cowboys featured three linemen who started at least 54 of 64 regular-season games. The most successful epoch of the Patriots' dynasty coincided with their greatest stability up front, with tackle Matt Light and guard Joe Andruzzi combining to start 121 of a possible 128 games between 2001 and 2004. 

This is good news for the Eagles. In Lane Johnson, they have a 28-year-old blue-chipper who will be a fixture on the edge for years to come. At guard, 29-year-old Brandon Brooks is another plug-and-play piece who projects well into the future.

The extent of the unit's potential will depend on finding a replacement for Jason Peters whenever he finally calls it quits, as well as the slope of the aging curve for 31-year-old center Jason Kelce. 

The offensive line led by Lane Johnson (left) and Brandon Brooks will be crucial for the Eagles’ success going forward.
YONG KIM / Staff Photographer
The offensive line led by Lane Johnson (left) and Brandon Brooks will be crucial for the Eagles’ success going forward.

•••

Beyond the glaring similarities among the men playing quarterback and those keeping him upright, there is something more abstract in play when you look toward the longevity that the greatest of the great winners have achieved. There is a continuity of message, of leadership, of scheme, an ability to find players of a certain archetype of mentality and fit. You think of Chuck Noll's Steelers, and Bill Walsh's 49ers, and Bill Belichick's Patriots, and you think of a certain type of player.

Perhaps the biggest unknown about the Eagles concerns their ability to replenish such players with each passing season.

This is particularly true on the defensive side of the ball, where identity is more of an egalitarian thing. On offense, the identity will largely remain a product of the man under center and the man calling plays.

The Eagles defense under Jim Schwartz is much easier to generalize: relentless speed on the line, aggressive confidence at the corners, unapologetic physicality in the middle of the field (currently taking the form of Jenkins). If Schwartz ever gets another chance at a head coaching job, will the Eagles struggle to maintain their identity the way they did after Jim Johnson departed?

And then, there's that Golden Equation, that internal battle fought by any man who has ever achieved something. For 2018, the first year of this new era, the result of that war is the most interesting question.

"I think the biggest thing is understanding that this team is going to be different than last year's team," Jenkins said. "We have new guys, just the dynamics of it all is different. And so we can't expect to have those same results by just walking on the field. You've got to treat being 13-3 the same as being 9-7."

It's worth noting that, this week, visitors to the Eagles' locker room will notice something different. That wall in the back of the room? The one celebrating the trophy? It is empty now. The picture is gone.

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