Thinking like a moss :)

Two days ago as I was derping around the web (not surprising at all), I discovered this awesome open course called "Critical reasoning for beginners". What's all about? The title does not say much to me, as I simply cannot catch what's so critical about reasoning. However, the content is circling around the nature of arguments and how by using logic and simple structuring rules to make your arguments stronger.

What's nice about all that stuff is, that even from the first lecture, one learns a lot of definitions formulated in "human understandable language" ( I mean, not only with symbols, as we learned it in the formal systems course, e.g. P or !P = true ). Besides, the lecturer has soooo amazingly wonderful beautiful amusing British accent, which might be the real reason for me listening to the lectures. Btw, she started the lecture with part of a Monty Python sketch (this one)!

Here's some interesting stuff: we are somehow used to say that an argument is true or false. But arguments cannot be true or false, they can be simply good or bad. The premises of an argument can be true or false, for example, but not the arguments themselves. And the good arguments are truth-preserving, because they can preserve the truth of the premises in the conclusion.

There is also this interesting statement I very much like: "There are only 2 sorts of things that can be true or false in this world. One of them is beliefs and the other is the sentences we use to express beliefs." At first, I was little bit confused, because beliefs are kinda subjective. But later on, it became clear, that there is a difference between religious beliefs, etc. and the term belief in the philosophy.

Also, I found out, that there are levels of abstraction and often the reason for a bad argument is when you are not able to make the difference between those. The clarity of thoughts is a consequence of not confusing those levels. And there's a very nice example:

Let's use chair, concept of chair and "chair". Saying that chair has 5 letters is not true, because chairs don't have letters. It also does not make sense to say that the concept of chair that someone has in mind has 5 letters. Therefore saying "Chair has 5 letters." makes sense only when chair is seen as a word. And that's definetely different abstraction level from the first two.