Common Logical Fallacies

Forms of Begging (ignoring) the Question ( reasoned argument)
(petitio principii)

The Ad Hominem Fallacy ( as opposed to the Ad Hominem argument). Attacking the opponent rather than dealing with his argument.

How could a known drug user advocate legalizing drugs?

Anyone can who can present an argument for doing so.

The Straw Man--Attributing to your opponents what they never asserted or citing another (weaker) argument for a position they did assert and attacking them on the words you put in their mouths.

You who want to impose a waiting period for the purchase of handguns take away guns from law abiding citizens and leave them only in the hands of criminals. A wait isn't an appropriation

Assuming your conclusion--How can we condone the white coated murderers who perform abortions? Murder is a crime. Abortion isn't.

Shifting the burden of proof. If you make an assertion, you must provide the reason for it.

There's no proof the CIA didn't kill JFK.

Hasty generalization--Not enough or non-typical examples in support of a broad conclusion.
My wife cheated on me. I'll never trust women again.

Confusing the merely consequent with the caused(post hoc ergo propter hoc).
The stock market crashed because the senate rejected the president's supreme court nominee.

The Either/Or fallacy. There are rarely two mutually exclusive alternatives to any question.
America: love it (don't criticize it), or leave it.

The Fallacies of Conditional Reasoning:

The Fallacy of Affirming the Consequent:
If it's rained (antecedent) then the street is wet. (consequent)
The street is wet, therfore it's rained.
There could be another reason for a wet street.

The Fallacy of Denying the Antecedent:
If it's rained, the street is wet.
It hasn't rained, therefore the street is not wet.

Simple Non Sequiturs, i.e. conclusions which don't follow from the reasons.

Almost all child molesters own pornography. Let's ban it.

Argument from Analogy(as opposed to explanation through analogy)No conclusion can be reached on the basis of an analogy.

In defense of terrorism for the sake of a revolutionary cause one hears "You can't make an omelette without breaking eggs."

Politics and cooking aren't equivalent arts.

The Ad Populum (from popular mores) Fallacy.

Everyone always has and always will cheat on their income taxes.
It must be OK.

Morality has at no time been subject to a vote.

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