Can anyone explain how the following statements demonstrate Post hoc thinkning and confuse correlation and?

Question

cause-effect?

1. Our city now has many immigrants from Latin American countries. the crime rate in our city has increased. Latin American immigrants are the cause of the crime wave.

2. The divorce rate has skyrockted. More woman are working outside the home than ever before. Working outside the home destroys marriages.

3. A high percentage of people in Dixville have developed cancer. the landfill, used by XZY Industries, has been located in Dixville for twenty years. the XYZ landfill has caused cancer in Dixville residents.

can someone help me i been working on this all last night for 5 hours and havent got anywhere?

Answer 1

"Post hoc" is short for "post hoc ergo propter hoc" which is Latin for "After which therefore because of which."

Here's another example of this fallacy:

Roosters crow just before the sun rises.

Therefore, roosters crowing cause the sun to rise.

All of these sentences conclude that Event A caused event B.  It is false (invalid) to assume that just because Event B happens after Event A, that B is caused by A. It's also false to assume that two events happening at the same time are related to one another at all. There are at least 3 other explanations:

1. Event B caused event A - a reverse cause-effect

I think your sentence #2 could be this, as well as the rooster sentence.

2. Both events are caused by something else.

3. Events are entirely unrelated.

Sentence #3 could likely be this, since cancer clusters often appear randomly.

Your sentence #1 is also an ad hominem argument ("againt the man") because it's blaming crime on the ethnicity of the cities newest residents, when in fact the crime rate is most likely attributed to poverty, overcrowding, or perhaps even by older residents taking advantage of newer immigrants.

Here's a good site about fallacies:

http://www.fallacyfiles.org/index.html