First, Glenn complained:
<<Why should they have to be the only ones to prove their point? Why are
anti-evolutionists exempt from having to justify their position? What you
are asking is the impossible. Since logically it is very difficult to prove a
negative (it can't be done), it seems that it would be more fruitful for the
anti-evolutionist to prove the positive i.e. that there is a limit to
variation. No one can prove that there is NO limit because that violates the
laws of logic. But you as a believer in limits, should be able to prove the
extent of variation.>>
Gordie opined:
<<It seems to me that the real difficulty in the present discussion has to
do with the imprecision of the use of the word "limitation". How limited
are morphological changes?>>
In answer, we need to be clear about what a "burden of proof" actually is. It
is nothing more nor less than the "duty of affirmatively proving a fact or
facts in dispute on an issue...[and is] not to be confused with prima facie
case." So even before we consider points of "imprecision"--the prima facie
standard--we can easily dispense with the burden issue.
Here, Glenn trips up over misuse of the terms "positive" and "negative." The
issue is as follows: Given the data, which everyone agrees shows large gaps in
developmental morphology, the question becomes "How does large scale change
happen?"
The "limits" person asserts a negative: Nature cannot account for it. Why?
Because it is "perverse" NOT to hold this position in view of the fact that NO
(nada) scientific paper has ever been published to give any support to the
natural development of complex biochemical structures.
The "no limits" person steps up and asserts there IS good reason to believe
otherwise. Very well. That is a positive claim. What are the good reasons? You
have assumed the burden. Sorry, but them's the breaks. And this is not asking
for proof that there is "NO limit" [in violation of "the laws of logic"]. It
is asking for the "good reasons"--the experimental data--which would allow a
person to reasonably hold the position that nature can account for the genetic
change required to account for the pattern of life. Absent those reasons, it
is UNreasonable to hold such a position (and thus the fallback into the a
priori assumptiveness Professor Johnson has so ably exposed).
So, the ball, as they say, is clearly in the "no limit" court. Thus far, there
has been no return of serve.
Jim