The talent of their personnel. A collective attitude that has a record of not giving in to adversity. The ability to go get top-shelf help when top-shelf help is needed.
The Mets have the NL's best record and a decent, if not overwhelmingly comfortable, lead in the NL East. This is not quite enough for some of the true believers, who recall last year's dominance and believe that this team comes up short in comparison. But it may all be relative. The Mets are not a push-button operation, but they may not have to be to reach all the way to the World Series.
Still, late August is no time to let complacency pay a visit.
"It's push time," manager Willie Randolph said on Tuesday. "It's the time of the year when you have to go on a nice streak. Hopefully, that's where we're headed."
They were headed that way on Tuesday night, with their fourth straight victory, a 7-6 thriller over the San Diego Padres. They accomplished the rare feat of roughing up both Chris Young and Trevor Hoffman in one cold and damp Shea Stadium evening.
Young came into the game leading the Major Leagues with a 1.93 ERA. He's been as good as he is tall, and he's 6-foot-10.
But this did not stop Carlos Beltran from driving in four runs against him -- two with a home run and two with a double -- on his way to a five-RBI game. Young departed after five innings, with a 2.12 ERA and a back problem. It wasn't as though he had been kicked around mercilessly, but the Mets had made their point.
Not only did the Mets get Young, they beat Hoffman with a two-run ninth-inning rally. Hoffman has 513 lifetime saves. His credentials are in order. This was the daily double of beating excellent pitching.
This had the feel of an important victory, particularly against a Padres team that is currently in a tie for the NL Wild Card lead with the Phillies. This would be the right time to start peaking. And it has not been all bliss this summer for the Mets. They have not had the kind of run production up and down the lineup that they had envisioned. There have been more shortcomings in the bullpen than they would have hoped. Their 71-53 record is not quite the 76-48 record that they had at this point in 2006, and their five-game lead is nothing like the 13 1/2-game bulge that they had last season after 124 games.
Still, these Mets have suffered a wave of injuries and have played through the whole deal without catastrophic results. Randolph sets the tone here, not allowing for the possibility of excuse-making. When the topic of injuries went on longer than he liked on Tuesday, Randolph used an old saying: "Don't talk about the labor pains, show me the baby.
"But I'm proud," Randolph added. "I love this team. We don't cry. We don't make excuses. We just play."
And look what happens when injuries hit the Mets at second base. They don't get a stop-gap or a fill-in. General manager Omar Minaya acquires in a trade a player of the first rank, Luis Castillo. Castillo was front and center on Tuesday night, driving in the game's winning run with a single off Hoffman.
"He has amazing speed, plate discipline, the ultimate two-hole hitter," said Marlon Anderson, who scored the winning run after reaching on a pinch-hit single.
"He's one of the best second hitters in the game," Beltran said of Castillo.
"He's a winner, that's the bottom line," Randolph said. "He's a guy who knows how to beat you."
Castillo's mastery of the small, but essential fundamentals of the game, Randolph said, was an example of a saying used frequently by bench coach Jerry Manuel: "Give to the game, and the game will give back to you."
That's the way it should be. Now, needing a right-handed bat off the bench, the Mets appear to have done exactly what needed to be done again, with the acquisition of the admirable and proven Jeff Conine.
"All the things you look for in a role player on a good team, he fits the bill," said Padres manager Bud Black. "The type of player he is, the type of person he is."
The fact that this has not been a dominant club should not suggest that it will not be a successful club. This isn't supposed to be easy, even if it sometimes appeared that way for the Mets last season. The core issue is not whether the Mets have slipped since 2006, but whether they can take one more step and be the NL's best team, from now through October. The available evidence points them in precisely that direction.
Mike Bauman is a national columnist for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.