What's the difference between humbler and mumbler?

Humbler

Definition:

(n.) One who, or that which, humbles some one.

Example Sentences:

(1) He acknowledged a charismatic mega fauna, like the dolphin, is probably worth more than a humbler animal, but he declined to offer a dollar figure.
(2) It sounds boring and wonky, but amounts to a situation in which, as the former Treasury advisor Jonathan Portes wrote last week , “owners of grand and very valuable properties pay little more than those in humbler abodes”.
(3) His decision to abjure the splendour of the apostolic palace in favour of the modest Casa Santa Marta guesthouse has offered proof of his personal commitment to a humbler church, while his tender embracing of Vinicio Riva, a man terribly disfigured by tumours , underlined his hands-on pastoral approach.
(4) But the origins of Warp Records, which celebrates its 20th birthday this year, were much humbler.
(5) Bishop's role as a pest controller started in 2005 in slightly humbler surroundings, when Ken Livingstone decided to rid Trafalgar Square of pigeons .
(6) Thomas Keneally photographed in London in 2007 Photograph: Eamonn McCabe Tom Keneally Tolstoy is one of those annoying people of genius who performed in the 19th century the ultimate tricks that the rest of us are now stuck with trying to perform imperfectly and on humbler scale.
(7) The Village in war-torn Mogadishu, Somalia, is a humbler affair and has just been attacked by Islamist militants, with a suicide attacker and car bomb killing at least 18 people.
(8) Bold and imaginative when it comes to getting more high-flyers into boardrooms, it has rather less to say to women clinging to humbler jobs by their fingernails (whose childcare subsidy under the Working Tax Credit is being cut).
(9) If you put it back where it should be, in Paris, it would be a more confident statement.” While this is true, the Galliano of 2015 is a humbler creature than the preening peacock of yesteryear who took his bows at Christian Dior shows dressed like a cross between Errol Flynn and Keith Richards.
(10) As the former first lady and secretary of state made her way to Iowa in a Scooby-Doo-inspired van to start her second presidential campaign, the founding members of “Obamadale” had a forceful message for a humbler Clinton: the liberal heartland’s support must still be earned – and even the frontrunner for the most powerful job on Earth can take nothing for granted.
(11) Against this backdrop, it is a moment to savour when any political authority shakes itself awake and demands that supersize companies respect rules resembling those for humbler beings.
(12) Instead he is likely to plump for the humbler, simpler title of Lord Glasman of Stoke Newington and Stamford Hill.
(13) No other European leader has risen from humbler beginnings – nor had so much stacked against them.
(14) There are campaigns denouncing the ethics of requiring young people already saddled with thousands of pounds of debt from their degree studies to do unpaid work, and debate over the morality of a system that allows those from well-to-do families to exploit their connections and secure opportunities that give them even greater advantage over those from humbler backgrounds.
(15) It’s as if, for some business people, supporting charity is a hobby like gardening or watching their children play sport – something deliberately different in spirit, humbler and gentler from the work they do in the commercial world.