what kind of fallacy is this?

Question

If someone is stating something as their opinoin but provides no proof that this is ABSOLUTLY true-so it would actually be seen as their opinion. So basically putting something down as a fact but in all reality it is an opinion. what kind of fallacy is that?

Answer 1

This must be an example of the logical error of the "assumed premise" otherwise know as the "False premise" Wikepedia discusses this in a fascinating article:

"A false premise is an incorrect proposition that forms the basis of a logical syllogism. Since the premise (proposition, or assumption) is not correct, the conclusion drawn may be in error. It is important to note, however, that the validity (in the technical, rather than popular sense) of an argument is a function of its internal consistency, not the truth value of its premises.

For example, consider this syllogism, which involves an obvious false premise:

* If the streets are wet, it has rained recently. (premise)
* The streets are wet. (premise)
* Therefore it has rained recently. (conclusion)

This argument is logically valid, but quite demonstrably wrong, because its first premise is false - one could hose down the streets, the local river could have flooded, etc. A simple logical analysis will not reveal the error in this argument, since that analysis must accept the truth of the argument's premises. For this reason, an argument based on false premises can be much more difficult to refute, or even discuss, than one featuring a normal logical error, as the truth of its premises must be established to the satisfaction of all parties.

Another feature of an argument based on false premises that can bedevil critics, is that its conclusion can in fact be true. Consider the above example again. It may well be that it has recently rained, and that the streets are wet. This of course does nothing to prove the first premise, but can make its claims more difficult to refute. This underlies the basic epistemological problem of establishing causal relationships.

[edit] Examples

* An example of a false premise occurs in The Simpsons episode "Much Apu About Nothing." After the town of Springfield suffers from a "bear attack", a Bear Patrol task force is installed to keep bears out of the town:

Homer: Not a bear in sight. The Bear Patrol must be working like a charm.
Lisa: That's specious reasoning, Dad.
Homer: Thank you, dear.
Lisa: By your logic I could claim that this rock keeps tigers away.
Homer: Oh, how does it work?
Lisa: It doesn't work.
Homer: Uh-huh.
Lisa: It's just a stupid rock.
Homer: Uh-huh.
Lisa: But I don't see any tigers around, do you?
Homer: Lisa, I want to buy your rock.

* Another example of this fallacy emerges in the daily discourse of American politics. The Bush administration's foreign policies are often defended with the argument that “The U.S. hasn't had another attack on our soil in five years (since 9/11), so they must be doing something right.” This is false because it not only ignores the fact that eight years passed between the 1993 World Trade Center bombing and the September 11th attacks, but it also ignores any other possible reason why we have not been attacked again. This form of logic could be used to claim that “We haven't been hit by any meteorites in thousands of years, so NASA must be doing something right.”

Hope this helps.

Answer 2

This is done by people on both sides of nearly every issue, every day, in the media.

Is there any such thing as ABSOLUTE proof?