I read the rest if the post and it makes no sense. The father story is non-sequitur, and this can only be interpreted as the poster not knowing how fences work: "you'd be looking at having to fence in the entire space you want the dogs in because the gap you'd leave would have to be big enough for a dog."

A sibling comment pointed this out, too: https://news.ycombinator.com/item?id=50105376