I guess the guy really did, that he did as the bible says and that he fathered the Jewish nation, fathered by extension Islam and Christianity as well. Maybe he really did, because well, we have that trinity of belief systems existing that we cannot deny.
Pretend with for a moment that he never did though. Lets pretend that the Jewish nation never came to be, that the Koran thus never got written, that the OT never got written, there was no jewish saviour prophecies uttered and that humanity made it through the last 4000 years or so without either of those three and their offshoots like christianity.
What would history be like?
We would have seen many wars, just none where christians, Muslims or Jews were involved in.
We would have all the eastern and oriental religions still, and a good many of those had/have real great morals and values.
We would have still the native, aboriginal peoples and their animal worship or whatever.
I have no doubt that Rome would have been what it was, the ancient cultures with their culture and learning would still be there.
Countries may be named differently, explorers would have had to fund their own shows.
I also have no doubt that the industrial revolution would have still occured at some point in time, maybe sooner, maybe later but still would.
Modern science and medicine would have still happened.
Although all of them differ, they still have codes of conduct, laws, punishment, morals, ways to care for family, a sense of community.
My point that I hope i am making soundly is that if the big three had never come to be, the world would be essentially the same. People being born people dying, nations rising and falling, the way of humanity would still be soldiering on, some parts of the globe would be in famine others in plenty, some would be wracked by war some would be in peace. Such is the way of humanity.
My argument? The big three have not done ANYTHING significant to change the world, to make it a better place!
I argue that in fact the world might just be a better place had Abraham not existed.
Yes, if NOW the big three disapeared in a big puff of smoke or the UN crushed them all out of existance we would notice a huge vaccume. But I also think it would be very quickly filled by perhaps a fresher breath of air for humanity too.
For three religions claiming to be almighty gods chosen ones, and who have dominated so much of the worlds recorded history, they have failed mankind in such big ways they they should all close themselves down in shame.
The 'some good' thay they have done, is no greater than that of other cultures that have not been jewish, Muslim or Christian.