Do you mean to say he falls down the mountain as he’s beginning to follow the path up?
I think The Raven nailed it before I got to reply. Gravity sucks and without gravity this poor gentlemen wouldn’t have bounced his way down the mountain.
Wait a moment -
He said he was going to RETRIEVE firewood. Perhaps he was searching for the same wood he had burned the previous evening? Meaning, he was chasing smoke, which, of course, goes up? Up the mountain? So high he chased it to the top and went over?
Ignore me.
Ah, but Feynn, without gravity we’d all suddenly float off into the sky, which would be kind of cool. Until the lack of air killed us or we got sucked into a jet engine intake.
So, was I half right or just clever?
Most of the people here seem to be trying to figure out, Why did he trip?, not Why did he die?
Sledman: Did his tripping directly cause his death?
Was he tripping, as in like high as a kite on acid or something, thought he could fly, and jumped off the mountain to his squishy death?
If not, then I have no idea!!!
Bye 
I know this one…the solution is ** MONKEYS.**
The solution is ALWAYS monkeys
You see, the monkeys are evil. The way they walk around wearing the hideous little monkey pants…so high and mighty…oh yeah…they think they’re better than us.
Maybe they are better than us…it’s their attitude I don’t like. Damn monkeys.
Once…there was this monkey…and he flipped me the bird… I kid you not.
Then this miserable little cur, reached into his freekin’ monkey pants and pulled out a monkey gun. He gave me a wink, then let me have it.
He only winged me…and I’m completly over the entire ordeal.
So, in closing, the man fell trying to retrieve the firewood because of those little pants wearing goblin monkeys.
Thank you for your time.
Was there snow on the ground?
If so, did that cause him to trip?
Sqrl
He swallowed a fly.
(think about it)
OK…
To clear a few things up.
panamajack…
It was earth.
It was dawn.
The fire was for cooking and he was gathering the days wood.
He did not have to chop the trees down yet as there was still plenty of wood lying on the forest floor at this higher elevation.(nudge, nudge)
Raven…
Can’t give you half.(wink, wink) Very clever and you’re onto something.
You and Feynn might just get this.
Achernar…
It certainly was a contributing factor? (know what I mean, know, what I mean!)
Mr. Cynical…
If I am interpreting you correctly we may have a new leaderboard.
SqrlCub…
You tell me why he died…
Want a hint. Read the responses carefully!
Did the cause of his death involve extreme temperatures of some sort?
Okay … How long had he been on the mountain?
Less than a day? Less than a week? Years? All his life?
Love is like oxygen, you get too much you get too high. Not enough, and you’re gonna die.
Hmm…ok, maybe then he tripped over a log or stick lying on the trail, fell over the edge and was splattered all over the valley floor due to the forces of gravity. Dang, this is taking longer than I thought it would…
If you had any idea how long I spent online researching Marc Bloch, your head would definintely spin.
he died becuase the firewood tumbled down the hill and knocked him off his feet…thus him falling to his death
Who or what made the path? Or am I restricted to ‘yes/no’ questions? If so, Did the man or a member of his family make the path?
I pushed him. 
Was his death the result of an injury or injuries? For instance, if he died of a heart attack whilst rolling down the mountainside, then no.
If so, did the injury or injuries result from his having tripped? For instance, if he tripped, stood up, and then was shot by a sniper, then no.
If so, was the kind of injury he sustained the kind that one might normally expect to get from tripping? For instance, if he died from hitting his head on a rock, then yes. If he died from falling into a fire, then no.
He died from lack of Oxygen to the brain. All death eventually boils down to that.
Hmmm… So he went up the mountain to retrieve firewood. Trees don’t grow at higher elevations, so the wood must have gotten there in a rather exceptional manner.
Maybe the mountain USED to be a low-elevation forest, but a massive earthquake raised the forest into a mountain, uprooting many trees in the process (but not destroying a pre-existing forest path). The uprooting of the trees explains why there is loose wood on the mountain.
Just as the man is walking down the mountain, an aftershock hits. With the earth shaking, the man staggers around, trying to keep his footing. Unfortunately, he is unused to the amount of oxygen available at such a high elevation (after all, it IS a new mountain so he’s used to living at a low elevation). Dizzily, he trips over one of many above-ground tree roots. He tumbles down the mountain, and falls into a fissure created by the earthquake. The aftershock, still in progress, causes the fissure to close, crushing the man.
Whew!