When a proposition which requires proof is assumed without proof
Put simply, begging the question is a baseless assumption used to argue for a particular conclusion.
“A therefore B” is the basic workings of this argument, which is formally valid logic. Yet without any evidence to show A as true, the opponent must necessarily follow this argument up with “How do you know A is true?”. As obvious as this seems, it is notoriously easy to overlook an assumption when in the heat of a debate.
Without exception, this is the bedrock of every religious claim, as religion necessarily asserts knowledge of the truth without the pesky burden of evidence to muck up the works. This is what often makes religion appear so eloquent.
God created the universe.
As elegant and concise as this explanation of the universe appears, it explains nothing. One must explain what God is and how it was created, let alone provide evidence as to why they believe this god exists at all.
Same-sex marriage is wrong because marriage is a bond between a man and a woman.
The above defines marriage as between a man and a woman within the argument, yet makes no effort to explain why this is necessarily the only definition of the term. What precludes marriage from being defined as a legally binding sharing of expenses, or acknowledgement of healthcare and tax benefits? One must necessarily ask this as a follow up question.
Murder is a sin, therefore it’s wrong.
Without much thought this seems agreeable. Upon further reflection the question will arise, “What is sin and what makes it wrong?”
In summary, special pleading uses unproven assertions to prove conclusions, dragging a debate backwards rather than forward.
Debate tactics: Beware to nip this fallacy in the bud as it may be used as a red herring to prevent your argument from being presented. In this way, even a poorly reasoned argument is likely to garner more support than an argument not presented.
In formal debates this tactic is most effective as it uses up the opponent’s limited time in pointing out the fallacies. String enough special pleading arguments back to back and you will monopolize the debate. This tactic is what professional debaters such as religious apologists like Ray Comfort and William Lane Craig rely on.
If a debater with no evidence can list enough unsupported or false assertions in sequence, the audience’s eyes will have glazed over by the time their opponent has explained away each item, leaving no attention span, or time, left for the original argument. Audiences leave thinking the opponent had nothing to add, when in reality it is an exploit of formal debate structure which essentially mutes the competition.