When creating arguments, it is possible to produce fallacies. Generally a fallacy is considered to be a mistake, a bad argument, or even a deceptive or misleading one. It would be more accurate to consider a fallacy as a flaw in the argument that makes it invalid or unsound.
 
 When we talk about soundness (or cogency), we mean that an argument must be both:

For instance, a classic example is:

All men are mortal.
 Socrates is a man.
 Therefore, Socrates is mortal.

The argument is valid (as the conclusion is true based on the premises — that is, that the conclusion follows the premises) and since the premises are in fact true, the argument is therefore sound / cogent.

Here’s an example of an invalid argument:

All men are mortal.
 Socrates is a man.
 All men are Socrates.

While the premises are true, the conclusion doesn’t follow — making it invalid (and it’s also a fallacy called a non sequitur, as the conclusion does not follow logically from the premises used to support it).

Here’s another example that has become popular (you can find the original cartoon by Randy Glasbergen here):

Penguins are black and white
Some old TV shows are black and white
Therefore, some penguins are old TV shows

For the rest of the week, I’ll go through a number of logical fallacies, including videos and audio links for additional resources. As always, subscribe to the podcast and blogposts by visiting 365daysofphilosophy.com. If you’d like more exercises and bonus content, visit www.patreon.com/kyliesturgess.