Either you believe, or you don’t. There’s no middle ground if you’re an Eagles fan this season. Either you watched the preseason juggernaut and harbored instant visions of the Super Bowl, or you dismissed it all as a mirage, a meaningless display against teams that didn’t care.

The Eagles are talented enough to lead the NFL in wins, or they’ll be Chip Kelly’s first team ever with a losing record. Take your pick. For me, it’s a no-brainer. I think they will go 13-3 in the regular season. That’s right: 13 wins.

I’m not predicting a Super Bowl, even though that is the whole idea here, isn’t it? No, there are way too many unresolved issues before that forecast seems logical. For all I know, the Eagles will make it back to the big game, and New England will find another way to cheat.

Unlike most NFL teams, when so many variables go into preseason predictions, the 2015 Eagles offer only one season-defining question: Can Sam Bradford stay healthy? He has already demonstrated what he can do in Kelly’s offense. But will he get to do it for 16 glorious games, or will he fall victim to more physical misfortune?

My bet is, he makes it through the season unscathed. I like the odds. Doctors say there’s an 88 percent chance Bradford’s twice-repaired left knee will not suffer a third ACL tear. That’s almost 9 out of 10. Who bets against a number like that?

Now, there are plenty of other problems that could arise, including a new and equally devastating injury to Bradford, or issues with an overused DeMarco Murray, or a breakdown on that makeshift offensive line, or more woes in a still-vulnerable defensive backfield. Hey, Kelly himself could develop prickly heat. Who knows?

But I’m betting that the odds swing in favor of the Eagles. I’m betting that 55 years without a championship earns us a long-overdue break. I believe in the law of averages, which owes Birds fans a season without demoralizing injuries, without major officiating mistakes, without fatal coaching decisions.

I’m not predicting a Super Bowl, even though that is the whole idea here, isn’t it? No, there are way too many unresolved issues before that forecast seems logical. For all I know, the Eagles will make it back to the big game, and New England will find another way to cheat.

There are some predictions that do make perfect sense, though:

     • The Eagles will have the best offense in the NFL.

Bradford may not be the most elusive quarterback, or the most durable, but he runs Kelly’s offense brilliantly. Unlike his predecessor, Nick Foles, Bradford is decisive and accurate. In fact, Bradford is the Eagles’ best pure passer in recent memory.

Donovan McNabb, Randall Cunningham and Ron Jaworski all had stronger arms, but none had the touch of Bradford, who can zip the ball between defenders or loop it over them. There’s a very good reason why Bradford was the No. 1 pick in the 2010 draft. He has the potential, even now, to rank among the very best quarterbacks in the NFL. Just check the tape of the third preseason game in Green Bay. Amazing.

     • The Eagles will have the most improved secondary in the NFL.

Granted, this isn’t saying much because the Birds’ pass defense has been abysmal the first two years under Kelly. That record of futility ended the day he finally replaced overmatched defensive-backs coach John Lovett with Cory Undlin. Under Lovett, the secondary didn’t know how to cover passes. Is there a bigger indictment of a coach than that?

Ignore the terrific job of the defensive backs in the first three games of the preseason. Forget the pick-sixes, the acrobatic interceptions, all of it. None of those moments is as important as eliminating big plays, especially on third-and-long. The Eagles allowed 72 passing plays over 20 yards last season. That will not happen under Undlin.

     • The Eagles have their deepest roster in years.

No one in the NFL has depth at running back like the Eagles. Not one of the other 31 teams has two marquee runners like DeMarco Murray and Ryan Mathews, an all-purpose threat like Darren Sproles, and a breakout preseason star like Kenjon Barner.

In fact, the Eagles have so many weapons on offense, there’s no reason to fret over the losses of LeSean McCoy and Jeremy Maclin. Kelly has established a committee of young studs like Jordan Matthews, Nelson Agholor, Josh Huff and Zach Ertz (when he’s healthy) to go with that amazing backfield.

On defense, the front seven is among the best in football, with nose tackle Bennie Logan emerging as a star next to the extraordinary Fletcher Cox. The Eagles have three quality inside linebackers in DeMeco Ryans, Kiko Alonzo and Mychal Kendricks. That’s real depth at a key position.

It is no secret that this depth doesn’t extend to the offensive line, outside linebackers or the defensive backfield, but no NFL team is deep everywhere. Heck, the reigning-champion Patriots currently employ two Eagles’ rejects – Patrick Chung and Bradley Fletcher. Does anybody want those two stiffs back?

The strong suspicion here is that Chip Kelly, in his third NFL season, has answers to all of the major questions now, especially since this is the first roster not weighed down by the mistakes of deposed GM Howie Roseman. The roster Kelly shaped these past seven months is the most talented since the Super-Bowl season of 2004, and the coach himself is the most creative thinker in the game.

Philadelphia sports fans deserve the kind of team the Eagles will be in 2015 (and early 2016). After the failures of the Sixers, Flyers and Phillies, they deserve a winner with a real chance to do something special. The Eagles are that team.

With just a little bit of luck, they will win 13 games. Bet on it.

***

To grasp the full impact of Tim Tebow’s brief tenure as an Eagle, you needed to spend the past couple of weeks on the South Jersey beaches like I just did. He was, by far, the biggest topic of conversation. It’s safe to say no prospective third-string quarterback ever generated so much interest.

What makes Tebow’s brief tenure here even more unusual is that he never made an astonishing play, never uttered a controversial word, never did anything, really, to encourage the fascination. He was just Tim Tebow. That was enough.

Tebow even achieved something no other player has been able to do in coach Chip Kelly’s three seasons here. He got the coach to tell the unpleasant truth about one of his players. He inspired Kelly, the ultimate player protector, to admit that Tim Tebow did not have sufficient talent to play in the NFL.

“We didn’t feel like he was good enough,” Kelly said.

Remember, when the coach traded LeSean McCoy, he expressed nothing but admiration. The same for DeSean Jackson, Nick Foles, Evan Mathis, Patrick Chung, Bradley Fletcher or anybody else. Kelly doesn’t believe in publicly criticizing players; it’s not in his DNA.

And yet he did it with Tebow, for a very good reason. Because Tebow deserves nothing less than total honesty. Because Tebow is not your average ego-driven, back-stabbing, win-at-all-costs professional athlete. In a sports world riddled with cheaters and criminals, he is someone truly worthy of the hero worship often misappropriated to American athletes.

In the end, Tebow handled his release over the weekend with his usual sense of honor. He thanked the Eagles and Kelly “for giving me the opportunity to play the game I love!” His joy at playing football was obvious every time he touched the ball. It was infectious.

Tim Tebow deserved all of the attention he got on the beaches of South Jersey the past two weeks, and elsewhere in his four months as an Eagle, for one very simple reason. He proved that you don’t have to be a special player to be a special person.

And finally ...

     • Chip Kelly called Eagles fans “awesome” during a rare Eagles’ open practice last month. Is that why he has reduced the number of public practices from four to two since he got here in 2013? Is that why he goes months in the off-season without answering questions? Imagine how Kelly would act if he didn’t think Eagles fans were awesome.

     • Evan Mathis said he had an offer that matched the $5.5 million he lost when he forced his way out of Philadelphia. The guard also said, “It isn’t all about the money.” OK, then why did he demand a new deal two years ago? Here’s the truth: He did not have a matching offer – no way – and it has always been all about the money with him.

     • Let’s take a quick inventory of the NFL after Tom Brady’s four-game suspension for Deflategate was overturned last week. Commissioner Roger Goodell is inept; that fact is now a matter of public record. His bosses, the owners, don’t care how badly he does his job, as long as they keep making money. And Brady is still a cheater. He will remain so until he explains why he destroyed his cell phone, and the evidence in it. OK, any questions?

     • If you’re looking for a precise definition of consumer fraud, check out the fourth game of any NFL preseason. Fans are required to pay regular-season prices for a contest involving many players who will never survive the final cut. The league needs to reduce prices on this shameless excuse for a sports event, or get rid of it entirely.

     • The wife of Redskins GM Scot McCloughan actually suggested on Twitter last week Rthat ESPN reporter Dianna Russini performed oral sex to get her latest story in the ongoing saga of Robert Griffin III. Wow. Then the team tried to lie its way out of the mess. Wow again. Owner Daniel Snyder sure does run a classy organization, doesn’t he?