[js1138]

I suggest you go back to
http://www.freerepublic.com/focus/f-news/1487919/posts?page=944#944

and read past the first sentence.

[Question_Assumptions]

You can't derive history from structure. You can reasonably speculate that if you know the history of object A, and you find an object B that is very similar, then you know something about the history of B.

Is the disinction that you are trying to draw between "deriving" and "speculating" or are you trying to claim that you need a known history in order to speculate about an unknown history? I can't really tell because it's not clear to me.

With respect to the first point, speculation does not disqualify something from being science. With respect to the second point, it's possible to reasonably speculate about the history of an object without having a known history or example to compare with by looking at its form and features.

Or are you trying to make some other point?