Fallacy: Two Wrongs Make a Right

Here are some examples I could find in my social life:

1. I have borrowed amir's expensive pen, but found I didn't return it. He tell's himself that it is okay to keep it, since I would have taken his.


2. After leaving a store, Maryam notices that she has underpaid by $10. She decides not to return the money to the store because if she had overpaid, they would not have returned the money.


3. 
   Amir is horrified by the way the state uses capital punishment. I said that capital punishment is fine, since both of us don't have any qualms about killing others.

Affirming the Consequent

when i go home sometime I am alone by that I mean none of my home mates are in the house and sometimes they both are inside so I am not alone.

• 
  If they are not inside they are outside.
  


• They are outside
  


• Therefore, they are not inside.
  

The above argument may be valid, but only if the claim "if he's outside, then he's not inside" follows from the first premise. Even in such a case, however, the validity stems not from affirming the consequent, but from the form modus ponens.

Begs the Question

I will try it again with another behaviour of my homemate:

• Amir is not lying when he speaks.
  


• Amir is speaking.
  


• Therefore, Amir is telling the truth

Although these statements have a logical form, they do nothing to convince one of the truthfulness of the speaker because the matter (that is, what the words actually symbolize) of the major premise (the general supposition Amir does not lie when he speaks) and the conclusion are actually the same thing. In seeking to prove Amir's truthfulness, the speaker asks his audience to assume that Amir is telling the truth, so this actually proves "If Amir is not lying, then Amir is telling the truth." Such arguments are formally logical. That is, the conclusion does formally follow; however, since it is materially identical to the major premise, the argument is said to be materially invalid. All self-circular arguments have this characteristic: that the proposition to be proved is assumed at some point in the argument.

Ad hominem fallacies

Lets try on this sentence I have catch out from a movie called unfaithful.

"You claim that this man is innocent, but you cannot be trusted since you are a criminal as well."

Now let's try working on it:

This argument would generally be accepted as reasonable, as regards personal evidence, on the premise that criminals are likely to lie to protect each other. On the other hand, it is a valid example of ad hominem if the person making the claim is doing so on the basis of evidence independent of their own credibility.

Now give me your comment to see what you got from it.

Fallacy

When it comes to fallacy I decided to ask my homemate to give me a example in order I could analyze it to fallacy. Below is the example:

Behzad argues:
Cheese is food.
Food is delicious.
Therefore, cheese is delicious.
This argument claims to prove that cheese is delicious. This particular argument has the form of a categorical syllogism. Any argument must have premises as well as a conclusion. In this case we need to ask what the premises are—that is, the set of assumptions the proposer of the argument can expect the interlocutor to grant. The first assumption is almost true by definition: cheese is a foodstuff edible by humans. The second assumption is less clear as to its meaning. Since the assertion has no quantifiers of any kind, it could mean any one of the following:
All food is delicious.
Most food is delicious.
To me, all food is delicious.
Some food is delicious.
In all but the first interpretation, the above syllogism would then fail to have validated its second premise. Amir may try to assume that his interlocutor believes that all food is delicious, if the interlocutor grants this then the argument is valid. In this case, the interlocutor is essentially conceding the point to Amir. However, the interlocutor is more likely to believe that some food is disgusting, such as a frog's liver white chocolate torte; and in this case Amir is not much better off than he was before he formulated the argument, since he now has to prove the assertion that cheese is a unique type of universally delicious food, which is a disguised form of the original thesis. From the point of view of the interlocutor, Amir commits the logical fallacy of begging the question.

Free writing...

Dude!
it may seems strange why I have choosen this images to describe but I think there is something in it related to critical thinking. Why there is a question mark in a mind of this person? why related to critical thinking?
It shows that humans don't know everything and they don't understand each part of every objective so they always looking to find some solution but also they think these solution are not enough so they woun't leave thinking about it and want to find the best solution so they go and do some research to find the best answer which could satisfy them.

What would happened if we didn't spend on computers

I was reading this text in a magazine that:

If people don’t invest in computers they are going to be left behind in the huge technological changes that are taking place. Computers are now much cheaper than they used to be. Most children feel entirely comfortable using computers.

now I would like to find if it is arguement or not:

• I'll put "therefor" at the start of the last one.

If people don’t invest in computers they are going to be left behind in the huge technological changes that are taking place. Computers are now much cheaper than they used to be. therefor Most children feel entirely comfortable using computers.

• Now I try to find a conclusion from the 2 reason:

I found it is impossible

So:

The passage above is not an arguement.