Yes. Passepartout gets to know Phileas Fogg much better as the book goes on. At first, Fogg seems mysterious, unemotional, and extremely predictable. But while traveling around the world, Passepartout sees that Fogg is also brave, generous, loyal, and willing to help others, even when it could jeopardize his journey.
By the end, Passepartout understands that there is much more to Fogg than his calm, reserved personality suggests.