But with both books open in front of me, I can't swear that the same person didn't write, or have a hand in writing, both of them. There's a similar flatness of style in each of them -- you might even be able to say a similar style -- and you could pick out passages that it would be hard to say definitely came from one book rather than the other.
But that's far from saying that the same man definitely wrote both books. There are enough people who convince themselves that whatever fits with their ideology just has to be true. I'd rather err on the side of caution, or at least hold back judgment a while, than be somebody who doesn't consider all the possibilities.
However, structurally, the two books, i.e. Ayer's acknowledged work and "Dreams of My Father" are so similar that it's actually more of a strain to assume that there were two different authors than not.
The vocabulary and phrasing are also eerily similar. Mighty fishy.