We have not a complete history in written language, but we have some very definite history in the rocks and hills and lands and seas.
There must have been people in the world when Cain went to the land of Nod, for the Bible history says Cain took unto himself a wife and his wife bore him a son and she named the son Enoch, and she builded a city for her first born and the name of the city was called Enoch.
The world certainly is more than 5,919 years old. Read the record of time so plainly visible at Niagara Falls.
Niagara Falls eats away about two feet of rock in a century; the gorge is a good many miles long. At the present rate of erosion it takes 2,640 years to eat away a mile. Multiply that by the distance between the falls and Lake Ontario and you have an idea of how many years Niagara Falls has been at work.
Before Niagara Falls was in existence the country round about was under the sea; before that under glaciers; before that under the tropics, and I don't know how many times it has swung on its pendulum between Frigid, Temperate and Tropic Zones.
So you see we are getting lost in a labyrinth of mystery when we take these known facts concerning the earth's age and try to definitely set any particular number of millions of years as the old world's age.