Difference between revisions of "Talk:1545: Strengths and Weaknesses"

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(predicate logic geekery)
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I'm also not sure how likely either of these are.[[Special:Contributions/108.162.215.100|108.162.215.100]] 20:29, 1 July 2015 (UTC)
 
I'm also not sure how likely either of these are.[[Special:Contributions/108.162.215.100|108.162.215.100]] 20:29, 1 July 2015 (UTC)
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: In your case (1), that means he will *both* be the ancestor to all people or to none. [[User:MGK|MGK]] ([[User talk:MGK|talk]]) 01:21, 2 July 2015 (UTC)
  
 
Also! Assuming Cueball hasn't had kids yet, he is already an ancestor to no living humans. [[Special:Contributions/108.162.215.100|108.162.215.100]] 23:47, 1 July 2015 (UTC)
 
Also! Assuming Cueball hasn't had kids yet, he is already an ancestor to no living humans. [[Special:Contributions/108.162.215.100|108.162.215.100]] 23:47, 1 July 2015 (UTC)

Revision as of 01:21, 2 July 2015

For anyone who wants to take a stab at a more thorough (or better written) explanation of ancestry, the wiki pages for Identical_ancestors_point and Most_recent_common_ancestor helped me to start understanding the topic. I think its easy to jump to the conclusion that it is extremely unlikely that Cueball will be the ancestor of all living humans, however it isn't quite as intuitive as I believed. --Pudder (talk) 16:17, 1 July 2015 (UTC)

I don't understand, why would come a day that he is "either an ancestor to all living humans, or to none of them"? It's very possible for him to be the ancestor to some living humans forever Egoist (talk) 19:44, 1 July 2015 (UTC)

If you have lots of children, and then if people interbreed randomly, as time goes forward it becomes less and less likely that any randomly selected person is not one of your descendents. As probability of not goes to zero, fraction of yes goes to 100%. But, if you do not have lots of children, and your kids don't either, at some future moment you may have zero descendents, and after that statistics cannot save you. Pesthouse (talk) 22:36, 1 July 2015 (UTC)

Two cases that haven't been dealt with: 1.) Humanity gets wiped out before this happens, so there are no living humans for Cueball to be ancestor to tor not. (0/0 case)

2.) Through physical separation, humanity diverges into 2 or more species, and Cueball is only an ancestor to some of these different species. Would all of these species be considered humans? I'm not familiar with the semantics.

I'm also not sure how likely either of these are.108.162.215.100 20:29, 1 July 2015 (UTC)

In your case (1), that means he will *both* be the ancestor to all people or to none. MGK (talk) 01:21, 2 July 2015 (UTC)

Also! Assuming Cueball hasn't had kids yet, he is already an ancestor to no living humans. 108.162.215.100 23:47, 1 July 2015 (UTC)