Logic is fundamental to most of humanity’s knowledge, but there are common fallacies in logic and reasoning, errors of judgement which happen due to:
<ol>
<li>Our assumptions based on what we see and deduct around us.</li>
<li>The mistaken thinking that logic is always intuitive.</li>
</ol>

Logical Fallacies

When a logical argument is not going anywhere, one party can sometimes try to win brownie points by appealing to an outside authority, the majority, or even towards feelings of pity.
Outside influences are a powerful force of nature in these hyper-social times, and most of us want to be part of a high-status community, making this fallacy extremely common.
Example: “The president said it’s true, so it must be true!”.

Appealing To Some Outside Authority

A common argument tactic online, Ad hominem is when instead of giving a response to the argument, the person is attacked in a personal way, leading to the focus being the kind of person he or she is, rather than the actual content of the (now forgotten) argument.
The Ad Hominem fallacy is can be observed during political debates: candidates routinely utilize it to their advantage and launch personal attacks on opponents.

Ad Hominem

Many arguments are distorted, exaggerated or misrepresented, sometimes beyond recognition, to mean something else that can be easily attacked.
This is called the “straw man” fallacy because, like replacing a real person with a person made of straw, you’re replacing a stronger argument with a weaker one in order to more easily discredit it.

The Straw Man

While engaging in an argument or debate, red herrings are certain statements or points that seem relevant to the core issue but are merely distractions. Red herrings themselves can be logical fallacies due to the factor of correlation and causation.
Example: While arguing about having a vegetarian diet amounting to being ethical, a debater mentions Hitler, an alleged vegetarian, and how he wasn’t ethical.

The Red Herrings

“You are either with us or against us!” Oversimplification of options, due to selectively providing a limited set of options and not encompassing other potential options creates a false dichotomy.
Example: Either your name is Ron or your name isn’t Ron is a true dichotomy, as it has two legitimate options. But saying that either your name is Ron, or you are an idiot is a false dichotomy.

False Dichotomies

This logical fallacy occurs when one’s own assumptions are used to establish their argument and prove it to be true.
Also called circular reasoning, this fallacy leads the person to follow the logic because a certain logic (which may be subjective or even entirely false) is already established.

Begging The Question

The Slippery Slope fallacy is a mistaken belief that one relatively mild unaddressed problem or allowance will automatically lead to other negative consequences.
The mind races on to the next negative consequence like a downward spiral, creating fear and anxiety.

The Slippery Slope

If two incidents or things happen at around the same time does not mean that one thing is the result of the other. Often many things occur at the same time yet are completely unrelated. 
A correlation of data, like:
1) Increase in social media usage, and
2) Increase in anxiety and depression
does not mean that one set of data is caused by the other.

Correlation And Causation

Logical fallacies are incredibly common in our everyday lives. Here are some of the worst ones we all fall prey to.