Argument from the Negative

The Argument from Negative occurs when:

1. burden of proof is improperly placed on the wrong party in an argument. 

2. one conclusion is clearly incorrect, so the arguer hastily jumps to another conclusion even though there are other plausible conclusions that haven't even been given fair consideration.

Example:

Cliff: That blurry trail camera picture is of a Bigfoot.

Matt: How can you say that? It could just as well be a bear.

Cliff: You can't prove that it's not a Bigfoot, so I'm calling it a Bigfoot.

Who has the burden of proof here? Also, this might be a good example of Occam's Razor.

Example: 

Summer is not the best season; therefore, winter must be the best season.

Notice how spring and autumn have been suspiciously omitted from the discussion?

Example: 

2+2≠5; therefore, 2+2=7.

Clearly, our arguer just wants to come to the conclusion that 2+2=7. Perhaps, they have an agenda and hope to make a lot of money off of this conclusion. 

Obviously, a plausible answer is not even being considered here.