What's a real-life example of using reason (and sound & valid) and coming up with a false statement of reality

In other words, I'm trying to find examples so that I can prove that reason is not always a reliable way of knowing and that we may need other ways of knowing.


So far I can only think of Xeno's Paradox and how with reason we can prove that motion is impossible, but with empiricism we can prove this isn't true.


Any others? Thanks so much!What's a real-life example of using reason (and sound %26amp; valid) and coming up with a false statement of reality
So long as a statement is BOTH valid AND sound, it cannot, by definition, be false. To claim otherwise is to defy the definition.





';A deductive argument is said to be valid if and only if it takes a form that makes it impossible for the premises to be true and the conclusion nevertheless to be false. Otherwise, a deductive argument is said to be invalid.





A deductive argument is sound if and only if it is both valid, and all of its premises are actually true. Otherwise, a deductive argument is unsound.';


http://www.iep.utm.edu/v/val-snd.htm





Therefore, if someone gives you an example, it NECESSARILY is a false example. No true example can exist except in contradiction to the rules.What's a real-life example of using reason (and sound %26amp; valid) and coming up with a false statement of reality
Reason is only a tool. It is entirely rational to think that the Earth is at the center of the Universe, because until the invention of telescopes people firmly believed that the Sun and the other stars and planets rise in the East and set in the West. This was an example where reason needed to be corrected by facts.


Reason is heavily influenced by bias, often competely subconsciously. If you simply dislike Muslims, you will find every scrap of evidence you can to prove that they are despicable, while brushing aside all positive reports as baseless or ignorant.


Human reason is therefore a tricky thing.
Zeno's paradox is an example of an unsound argument, so that's not going to get you what you seem to be looking for. If you mean sound and valid like every other logician means sound and valid, then you won't be able to find a sound and valid argument that has a false conclusion. By definition, an argument cannot be called sound unless it is valid AND its premises are true, and it cannot be valid by definition unless the conclusion is true EVERY TIME its premises are true. So looking for a sound and valid argument with a false conclusion is definitionally impossible, it's like looking for a bachelor who is not an unmarried man or a vixen that is not a female fox (assuming you don't have some oddball definition of 'bachelor' or 'vixen'). Even if you had some oddball definition of sound and valid, it would be impossible to find something that fit your definition and did not fit it at the same time. You're butting heads with the principle of non-contradiction on this one.





Example of things that were once reasonable for people to believe don't really count because those beliefs were found to be the result of untrue premises, hence of unsound arguments.
THE RULES OF REASONING AND THE RULES OF NATURE ARE THE SAME.......YOU CAN MAKE REASONS FROM NATURE AS AN ADVICE





PEACE