From The Logical Fallacies of the Documentary Hypothesis, Chapter 1:
He has correctly entitled these categories “The Seven Main Arguments,” for arguments are the only evidence which he presents. Indeed, arguments are the only evidence which any documentarian presents, which means that their evidence is only as good as their arguments.
In general, arguments fall into two classes: deductive arguments and inductive arguments. A deductive argument consists of three parts: a major premise, a minor premise, and the conclusion. For example:
Major premise: All humans are mortal.
Minor premise: Plato is a human.
Conclusion: Therefore, Plato is mortal.
To be a sound argument, the premises must be true and the argument must be free of all logical fallacies. If the argument is sound, then the conclusion is necessarily true.
An inductive argument draws a general principle from a set of specific observations (its premises) and then applies that principle to a specific case (its conclusion). For example:
Observations: The New England Patriots have won all of the regular season and playoff games this year (which was true in 2007).
General principle: The New England Patriots are unbeatable.
Conclusion: The Patriots will win the Super Bowl this year (2007).
At best, even though its premises may be true and the argument may be free of all logical fallacies, the conclusion of an inductive argument can only be probably true, not necessarily true (and in this case, it was not true: the Patriots lost to the Giants in 2007). The strength of the argument depends on how many factors are involved in determining the outcome of the conclusion: the more factors that are involved, the less probable its conclusion. The strength of the argument also depends on its set of observations (its sample size): the larger the sample size, the more probable its conclusion. I was a student in a philosophy class in which a military officer argued that his gun will never fail him in the future because it had never failed him in the past. The rest of us argued that the history of all guns shows that guns eventually do fail, which means that his gun will fail him one day. He based his argument on a small sample size, the history of one gun (his gun). Our argument was based on a vastly larger sample size, the history of all guns. Still, his conclusion may have been the correct one: his gun may have been one of the few that never failed.
Of course, in our speech and in our writings, we do not present our arguments in the clearly laid-out formats used in the examples above. Doing so would quickly render conversation and the reading of literature mundane and boring. The alternative, however, easily allows for the camouflage of logical fallacies. This is not to say that the committing of logical fallacies is deliberately done. Sometimes it is, but often the arguer is unaware that he or she is committing a logical fallacy until the opponent identifies and exposes the logical fallacy, thereby exposing the unsoundness of the argument.
For example, the argumentum ad ignorantiam (argument from ignorance) or the appeal to ignorance fallacy occurs when the arguer says, “My opponent has not proven that my position is false. Therefore, my position must be true.” That the opponent has not successfully proven that the arguer’s position is false does not necessarily mean that the arguer’s position is true. It may mean that the opponent has not yet found the correct counter-argument or evidence to disprove the arguer’s position. Or the opponent may think that the position is so obviously false that it is not worth disputing.
Friedman commits this fallacy when, in his “Foreword” to the twentieth anniversary printing of Empirical Models for Biblical Criticism, edited by Jeffrey H. Tigay, he states,
Tigay discusses why it is called the Documentary Hypothesis in his introduction, referring to its hypothetical methodology (p. 2). Really, it is long past time for us to stop referring to it as a hypothesis. The state of the evidence is such that it is now—at the very least—a theory, and a well established one at that. To my mind, in the absence of any proper refutation of its strongest evidence, it is fact.
Friedman has not defined what he means by “proper,” so, for all we know, valid refutations have been made but have been dismissed by him as not “proper” in his opinion. However, even if no refutations have been made at all, it does not necessarily follow that the Hypothesis should now be promoted to fact.
No matter how Friedman defines a “proper” refutation, it should not include absolute proof that Moses did indeed write the Pentateuch. The conservative scholars should not be required to prove that Moses wrote the Pentateuch any more than the documentarians should be required to prove that they wrote their own works. Joel S. Baden does not have to prove that he wrote The Composition of the Pentateuch: Renewing the Documentary Hypothesis. Friedman does not have to prove that he is the author of Who Wrote the Bible? However, if I were to claim that Friedman did not write that book, that rather two other authors wrote documents that were then conflated by a redactor to form that book, the burden of proof would rest on myself. So, too, the conservative scholars should not be required to prove that Moses wrote the Pentateuch since the Pentateuch clearly says that Moses wrote it (Deut. 31:9, 24-26; more on this in Chapter 5). The burden of proof rests on the documentarians.
In that “Foreword”, Friedman claims that the proponents of the models that seek to overthrow the Documentary Hypothesis do not challenge
the newest strong evidence, namely: (1) linguistic evidence showing that the Hebrew of the texts corresponds to the stages of development of the Hebrew language in the periods in which the hypothesis says those respective texts were composed; (2) evidence that the main source texts (J, E, P, and D) were continuous, i.e., it is possible to divide the texts and find considerable continuity while keeping the characteristic terms and phrases of each consistent; and (3) as this book shows, evidence that the manner of composition that is pictured in the hypothesis was part of the literary practices of the ancient Near East.
These are the reasons why, in his mind, the Hypothesis should be elevated to the level of fact. The first line of evidence is also the first of his Seven Main Arguments. The second line of evidence here is also the fourth of his Seven Main Arguments. We will examine these two lines of evidence in Chapter 2. Later in the “Foreword,” Friedman will replace the third line of evidence with all seven of his Main Arguments.
Of the three arguments presented here, the third offers the best support for the Hypothesis. It also offers, as we shall see, the worst. In fact, it can be used to argue against the Hypothesis. But first, let us see why it offers support for the Hypothesis….
 For an excellent explanation of deductive and inductive arguments, as well as logical fallacies, see Robert Arp, Steven Barbone, and Michael Bruce, eds., Bad Arguments: 100 of the Most Important Fallacies in Western Philosophy (Oxford: John Wiley & Sons Ltd., 2019).
 Richard Elliott Friedman, “Foreword,” in Jeffrey H. Tigay, ed., Empirical Models for Biblical Criticism (Eugene, OR: Wipf and Stock Publishers, 2005. hereafter referred to as Empirical), ; the pages of the Foreword have not been numbered, so I have numbered them starting with . The book was originally published in 1985 by the University of Pennsylvania Press without the “Foreword.”
 Richard Elliott Friedman, Who Wrote the Bible?, 2nd ed. (N.Y.: Simon & Schuster, 2019, hereafter referred to as Wrote). All references are to this edition unless stated otherwise.
 Friedman, “Foreword,” in Empirical, .