What's the external and internal conflict in "A Sound of Thunder" by Ray Bradbury?

"A Sound of Thunder" by Ray Bradbury is a quick moving,
suspenseful short story. Conflict adds tension to any short story, and this one is no exception.
There are four types of
conflict:

External

1.
Man Vs. Man -- During their trip back in time, Eckels panics when he sees the
dinosaur and steps off the path, a huge mistake that could alter time. Travis, the tour guide, is
furious with Eckels and threatens to leave him back in the past. He
states:

"Stay out of
this!" Travis shook his hand away. "This fool nearly killed us. But it isn't that so much, no.
It's his shoes! Look at them! He ran off the Path. That ruins us! We'll forfeit! Thousands of
dollars of insurance! We guarantee no one leaves the Path. He left it. Oh, the fool! I'll have to
report to the government. They might revoke our license to travel. Who knows what he's done to
Time, to History!"

This Man Vs. Man
conflict adds tension between the two main characters of the story and adds to the suspense the
reader feels as to what they will find when they return to present day.

2. Man Vs. Nature -- This is the
conflict that Eckels feels with the dinosaur he encounters in the past. It is huge - far bigger
than he expected and he loses his nerve. Aside from the physical battle between the men and the
dinosaur, this conflict also overlaps with Eckels internal conflict, man vs. self.

3. Man Vs. Society -- This conflict is
what makes the novel interesting; it begins as a sort of backdrop, seemingly unimportant, but by
the end of the novel, Eckels' worst fear comes true and Deutscher is President. At the beginning
of the story, Eckels states:

readability="24">

"Makes you think, If the election had gone badly
yesterday, I might be here now running away from the results. Thank God Keith won. He'll make a
fine President of the United States." "Yes," said the man behind the
desk.

"We're lucky. If Deutscher had gotten in, we'd have the worst
kind of dictatorship. There's an anti everything man for you, a militarist, anti-Christ,
anti-human, anti-intellectual. People called us up, you know, joking but not joking. Said if
Deutscher became President they wanted to go live in 1492. Of course it's not our business to
conduct Escapes, but to form Safaris. Anyway, Keith's President
now.

This sets up another external
conflict that reappears again at the end of the story.

Internal

4.
Man Vs. Self -- This conflict is really the turning point of the story: Eckels
loses his nerve and panics, veering off the path and rewriting history. When he sees the
dinosaur, he states:

readability="11">

"Get me out of here," said Eckels. "It was never like
this before. I was always sure I'd come through alive. I had good guides, good safaris, and
safety. This time, I figured wrong. I've met my match and admit it. This is too much for me to
get hold of."

He has a moment of
realistic observation when he sees this dinosaur and is legitimately frightened. His veering off
the path is what causes the change in the future.