Suppressed Evidence

Intentionally failing to use information suspected of being relevant and significant is committing the fallacy of suppressed evidence. This fallacy usually occurs when the information counts against one's own conclusion. Perhaps the arguer is not mentioning that experts have recently objected to one of his premises. The fallacy is a kind of fallacy of Selective Attention.

Example:

Buying the Cray Mac 11 computer for our company was the right thing to do. It meets our company's needs; it runs the programs we want it to run; it will be delivered quickly; and it costs much less than what we had budgeted.

This appears to be a good argument, but you'd change your assessment of the argument if you learned the speaker has intentionally suppressed the relevant evidence that the company's Cray Mac 11 was purchased from his brother-in-law at a 30 percent higher price than it could have been purchased elsewhere, and if you learned that a recent unbiased analysis of ten comparable computers placed the Cray Mac 11 near the bottom of the list. If the relevant information is not intentionally suppressed by rather inadvertently overlooked, the fallacy of suppressed evidence also is said to occur, although the fallacy's name is misleading in this case. The fallacy is also called the Fallacy of Incomplete Evidence and Cherry-Picking the Evidence. See also Slanting.

Stacking the Deck

See Suppressed Evidence and Slanting.

Smokescreen

This fallacy occurs by offering too many details in order either to obscure the point or to cover-up counter-evidence. In the latter case it would be an example of the fallacy of suppressed evidence. If you produce a smokescreen by bringing up an irrelevant issue, then you produce a red herring fallacy. Sometimes called clouding the issue.

Example:

Senator, wait before you vote on Senate Bill 88. Do you realize that Delaware passed a bill on the same subject in 1932, but it was ruled unconstitutional for these twenty reasons. Let me list them here.... Also, before you vote on SB 88 you need to know that .... And so on.

There is no recipe to follow in distinguishing smokescreens from reasonable appeals to caution and care.

Slanting

This error occurs when the issue is not treated fairly because of misrepresenting the evidence by, say, suppressing part of it, or misconstruing some of it, or simply lying. See the following fallacies: Lying, Misrepresentation, Questionable Premise, Quoting out of Context, Straw Man, Suppressed Evidence.

Selective Attention

Improperly focusing attention on certain things and ignoring others.

Example:

Father: Justine, how was your school day today? Another C on the history test like last time?
Justine: Dad, I got an A- on my history test today. Isn't that great? Only one student got an A.
Father: I see you weren't the one with the A. And what about the math quiz?
Justine: I think I did OK, better than last time.
Father: If you really did well, you'd be sure. What I'm sure of is that today was a pretty bad day for you.

The pessimist who pays attention to all the bad news and ignores the good news thereby commits the fallacy of selective attention. The remedy for this fallacy is to pay attention to all the relevant evidence. The most common examples of selective attention are the fallacy of Suppressed Evidence and the fallacy of Confirmation Bias. See also the Sharpshooter's Fallacy.

One-Sidedness

See Slanting and Suppressed Evidence.

Lack of Proportion

Either exaggerating or downplaying a point that is a crucial step in a piece of reasoning is an example of the Fallacy of Lack of Proportion. It's a mistake of not adopting the proper perspective. An extreme form of downplaying occurs in the Fallacy of Suppressed Evidence.

Example:

Chandra just overheard the terrorists say that they are about to plant the bomb in the basement of the courthouse, after which they'll drive to the airport and get away. But they won't be taking along their cat. The poor cat. The first thing that Chandra and I should do is to call the Humane Society and check the "Cat Wanted" section of the local newspapers to see if we can find a proper home for the cat.

Incomplete Evidence

See Suppressed Evidence.

Cover-up

See Suppressed Evidence.

Cherry-Picking the Evidence

This is another name for the Fallacy of Suppressed Evidence.