Mourinho: Arsenal have the necessary belief
Arsene Wenger's men can return to the top of the table by beating Chelsea, who have the opportunity to go level on points with leaders Liverpool, at the Emirates Stadium.
Arsenal last lifted the Premier League trophy in 2004, prior to Mourinho's first spell in charge of Chelsea.
Yet the Portuguese feels his side now face a rival with greater self-belief, particularly after the arrival of Mesut Ozil from Real Madrid in the close-season.
"I think, in the deep of their souls, they (Arsenal) think they can (win the title). They believe they have the conditions to do it," said Mourinho.
"In my previous time here, (Theo) Walcott was a kid. He's now a man. Other players are in the best moment of their careers – (Jack) Wilshere, (Aaron) Ramsey and (Kieran) Gibbs.
"I'm not saying Mesut transformed the team completely. The manager and the club has given players conditions and time to have great stability in their evolution.
"And now, when you buy (Olivier) Giroud and now Ozil and some other players, the team becomes much better and ready to be doing what they are doing, which is to fight for the title."
Arsenal and Chelsea are currently two of four sides, together with Liverpool and Manchester City, separated by just three points at the summit.
Yet Mourinho believes City have missed an opportunity to pull clear of the pack.
"I think in normal conditions Manchester City should be far from the others because of the squad, the maturity, the stability of the players, the potential of the striking force, the experience of the players. There is a difference," he added.
"But the Premier League is being difficult for everybody, also for them.
"So in this moment, everybody is there. So, I think (it is) good fun."