In Jack London's naturalistic novella, Buck, a crossbreed of St. Bernard and Scottish shepherd, who has inherited the massive size of the St Bernard and the intelligence of the shepherd finds himself sold to men who train him to become a sled dog in the Yukon during the Gold Rush. Perrault, a French-Canadian, understands the sled dogs and knows full well that there can be only one alpha-male in these dogs of the wild who are not too far distant from their ancestral wolves.

With his exposure to such raw country and men, Buck returns to his atavistic instincts and recognizes the threats from Spitz, who snarls and bristles at Buck whenever possible. Perrault and Francois notice and Francois tells his partner,

“All de tam I watch dat Buck I know for sure. Lissen: some dam fine day heem get mad lak hell an’ den heem chew dat Spitz all up an’ spit heem out on de snow. Sure. I know.”

One night after supper, Buck returns to a nest he has made in the snow only to find Spitz has taken the spot. As they scuffle, Perrault steps in and uses his stick. However, while this dispute takes place, a hug pack of starving wild dogs descend upon the camp. As Buck is attacked by three huskies, Spitz nips at him.

He flung himself upon another, and at the same time felt teeth sink into his own throat. It was Spitz, treacherously attacking from the side.

One indication of Buck's vying for the position of alpha-dog is his threatening of Spitz’s leadership by siding with the weaker dogs on a run when Spitz tries to bring them into line. One day as Buck again leads the pack, Spitz breaks and runs across a narrow piece of land. Believing that Spitz is giving chase to a rabbit, Buck watches a Spitz kills his prey. Then, taking advantage of the moment, Buck charges for Spitz, but overruns him and misses his throat. Spitz regains his footing, charges and "slashing Buck down the shoulder." Now, the "time had come. It was to the death." In a brutal battle, Buck is "inexorable" and emerges as the victor, "making his kill and finding it good."

"Wh? Wot i say? I spik true w'en I say dat Buck two devils," Francois tells his partner, who also is not surprised. But, when he tries to make another dog the lead, Buck will not permit it; "he would not be content with less."

Nevaire such a dog as dat Buck!....Heem worth one t'ousn' dollair, by Gar! Eh? Wot you say Perrault?" Francois asks his partner.

And Perrault just nods his head in agreement. They are impressed with Buck and recognize him as a strong alpha-dog...."the dominant primordial beast."

How do François and Perrault react to Buck killing Spitz?

Buck had begun to act on his desire for the leadership of the team. And Spitz was in trouble because Buck "was preeminently cunning, and could bide his time with a patience that was nothing less than primitive." Once his dominance was called into question by Buck, the other dogs began to fear him less and so grew unruly and difficult.

So when Buck and Spitz finally fight to the death and Buck wins, Francois and Perrault are actually pleased that Spitz is gone. 

When Perrault said that Spitz fought like hell, “An’ dat Buck fight lak two hells,” was François’s answer." He went on: “An’ now we make good time. No more Spitz, no more trouble, sure.”

They were pleased that the leadership void had been filled and clearly had high hopes for how things would work out now that Buck was in charge. Soon the greatness of Buck would be even more obvious as he led the team with that same cunning and amazing power.

How do Francois and Perrault react when Buck kills Spitz?

In the novel Call of the Wild by Jack London, Buck is the main character who turns from a civilized, pampered pet into a wild creature willing to kill. Spitz, the lead dog of the team and Buck's nemesis, challenges Buck over a rabbit, the fight to the death begins.  Buck wins by using his imagination and changing a strategy midstream.  Spitz dies, and only Buck appears the next morning.  Both Francois and Perrault, two practical men, comment, "An' dat Buck fight lak two hells".   Francois says, "No more Spitz; no more trouble, sure." They simply comment on what cannot be fixed and plan to continue on.  When the lead dog's place is given to another dog, Buck refuses to be part of the team.  Francois and Perrault try to coax, to catch, to punish, to curse Buck into his usual place in the team which Buck will not do.  When he is given the lead dog spot, and the clubs thrown down, Buck becomes the new leader.  The two men react with resigned consent, and finally get the team on the trail.  Buck is now the new leader, a better leader than Spitz, and the two men are happy with the faster pace and controlled team.

How do François and Perrault react to Buck killing Spitz in The Call of the Wild?

In Chapter III, "The Dominant Primordial Beast," the urge to dominate is strong in Buck and until his new life in the Alaskan wilderness, this urge grows. Francois and Perrault recognize in Buck and Spitz that a rivalry will occur between the two Alpha dogs. "One devil, dat Spitz" remarks Perrault on one occasion when Spitz took advantage of Buck's exhaustion after he has fled mad Dolly. But, Francois rejoins, "Dat Buck two devils." This first attack of Spitz is the beginning of a tremendous rivalry as Spitz feels his supremacy is threatened by this bigger Southland dog, but he is a cunning dog.

"It was inevitable that the clash for leadership should come. Buck wanted it. He wanted it because it was his nature, because he had been gripped tight by that nameless, incomprehensible pride of the trail and trace....this was the pride that bore up Spitz and made him thrash the sled-dogs....

With his knowledge of these dogs, Francois knows that sooner or later, Spitz and Buck will fight until one is killed. While there are various confrontations among the dogs, Buck undermines the authority of Spitz as he sides with the weaker dogs. However, "cold and calculating" Spitz takes advantage of a rabbit chase to cut across the field and attack Buck. Soon Buck is bleeding, but he tricks Spitz and breaks his leg so that prevents his running and finishes him off. "Buck was inexorable."

In the next chapter, Francois underscores his remark that Buck is "two devils." He also remarks, "No more Spitz, no more trouble, sure." But, when Buck is not given the leadership position, he rebels. So, finally, Francois places Buck in the lead role and with his quick thinking and acting, Buck proves himself a superior leader to Spitz. Consequently, Perrault is satisfied, and Francois is even more impressed,

"Nevaire such a dog as dat Buck!" he cried. "No, nevaire! Heem worth one t'ousan'dollair, by Gar! Eh? Wot you say, Perrault?"

In these two chapters, Jack London's The Call of the Wild models the arguments of Nietzche about human competition as Buck is the domineering creature, "the dominant beast," who possesses "the will to power." London refers to Buck as a "masterful dog" who has "pride" and engages in the struggle for power, the "clash for leadership" of Nietzsche, for the simple reason that this drive, this innate desire, is simply a part of his "nature."