The cause of many of the most major problems in our lives is when people commit a logical fallacy.
Let me tell you what I mean.
The study of logical inferences, or the drawing of conclusions from a starting statement, known as an premise, using logic, hinges on the idea of a syllogism.
Here is a classic syllogism.
A. All men are mortal
B. Socrates is a man
I. Therefore Socrates is mortal.
The two statements, or premises, A and B are combined together to make the logical inference I. This is the basis of philosophical logic; it is the building block upon which the entire edifice of philosophy is founded. But as we shall see - also of everyday life. A poor understanding of the workings of the syllogism can lead us to make disastrous decisions, affecting not only ourselves, but others too.
A. All cats look grey in the dark
B. Felix is a cat
I. Therefore Felix looks grey in the dark
The first syllogism cannot be disputed, because the logic is faultless, AND the premises are true. In the second one, we could dispute it, not because there is anything wrong logically, but because we might disagree with one of the original premises (all cats look grey in the dark.)
What about this one?
A. All grass is green
B. My eyes are green
I. Therefore my eyes are grass
Can you see what is wrong with this one and how it is different from the correct one at the top of this post? If you can, then your logic is better than that of the Education Ministry of a small, populous and influential country on the north-west fringe of Europe. Their argument went like this: A survey of schools where students get consistently high grades shows that all of them set homework. So if the schools in the inner-city sink areas and in the ghettoes start to set homework and enforce it, then they too will have high grades. Yes, these people really did believe that! Their error can be seen in a simple syllogism.
A. All successful schools set homework to their students
B. Drug Street High School has started setting homework
I. Therefore Drug Street High School will start to be successful
This a bit like saying my eyes are grass. There's an episode in Alice in Wonderland where they had mistakenly planted white roses which were supposed to be red, so they painted them red. But sadly, this is the way governments work.
Another kind of logical fallacy, and one which is very dangerous in our society, leads people to fear those who are different in some way. For example, in their skin colour. An illustration of this fallacy is:
A. All the black men I have heard about are criminals
B. John is a black man
I. Therefore John is a criminal
When we write it in this way, the mistake becomes more obvious.
Perhaps if people took more notice of syllogisms in their thinking, the world would be a happier place.
Just to finish, here is a paradox syllogism:
A. All the men of the island of Crete are liars
B. I am a Cretan man
I. Therefore I am lying
If he is lying, how do we know that either of statements A or B are true? And if they are not true, how do we know that it's true that he's lying? And if it is true that he's lying, he must be telling the truth, so he's not lying, so it's....
AAAAh, no, I can't get my head round this!