Besides who are we to say that someone "should never have existed"!!! Whether you were born by accident or because a loving couple decided to have a child you have the EXACT SAME RIGHT TO EXIST DAMN IT!!!!
Yes.
How can someone know if someone is a accident or destined by fate to exist?
The only way to make such a determination and decide whether the existance of someone is accidential or not is to follow science.
And all the evidence of science indicates that either:
1) everyone and everything is completly random and accidential
2) everything and everyone is predetermined
3) everyone and everything is a mixture of predetermined and random, accidental factors.
And in al lthree case there is no possibility of separating accidential and random people from predetermined people, so everyone has to be considered to have equal rights.
I have an idea for a fictional character who is immortal and whose mission to save everyone, giving eternal life to every intelligent being ever born in the entire universe, including countless sets of peopel born in alternnate universes which are inconsistent . The people in alternate universe A will not be born if the people in alternate univers B are born, and so on. Andhis mission isto save them all. To use a lot of understatement, this chaacter has great job security.
Here's a question, though. If Sisko and the rest of the Defiant crew had decided on their own to avert the accident that sent them through time, erase the colony from existence... would that be murder? Or simply exercising the right to make their own fate?
If a woman chooses not to have children, and deleted three children, eight grandchildren, 19 great grandchildren, and 235,789 other assorted descendants born over the next few hundred years... is she a mass murderer?
She is certainly a mass murderer from the point of view of those descendants if they can learn about her decision to delete them from distance.
I note that there are only three classes of humans sorted by reproductive results.
1) Those who have no children.
2) Those who have children but their descendants die out within a few generations.
3) Those whose descendants continue until the end of their species. And after enough generations, each such ancestor will have so many descendants that every member of their species will be descended from them.
Suppose that a time traveller visits a group of hunter-gatherers living several times farther in the past than the period for someone's descendants to become the entire human population. Suppose that he somehow wipes out the entire group. Unless they would have all died without descendants anyway, some of them should have become the ancestors of everyone living in his era, including himself. So the time travellor will never have been born.
Suppose that a time traveller visits a group of hunter-gatherers living several times farther in the past than the period for someone's descendants to become the entire human population. Suppose that the entire little tribe is at the shore when the ocean suddenly recedes and they walk out on the seabed to gather stranded fish, but he warns them to run for high ground.and they do, and so survive the tsunamies which would have otherwise killed them all.
So some of them will become the ancestors of all people living in the time traveler's era. And to do that they will have to marry and have children with people who would have otherwise married and had children with different people. So after thousnds of years their descendnts will completely replace the total population of humans. And thus the time traveller will never have been born.
Think about mcrosopic life forms and how short their generations are and how many generations they have in one human generation. And which lifeforms have the greatest impact on how long humans live? Microscopic bacteria and viruses.
So suppose that a time traveller travels thousands of years in the past and breathes once before returning to his own time. He will bring specimens of long extinct bacteria and viruses back to his own time. And he will take specimens of the bacteria and viruses of his own time into the past and relese them when he breathes.
That will change the evolution of bacteria and virus species in the past. And that will change the evolution of new deadly diseases from previously harmless germs. Thus a number of diferent peole will live or die than would have. And so by the time the time travller came from, there will be a completely different set of living humans. And thus the time traveller will never have been born.