LOGIC V/S COMMONSENSE

 LOGIC V/S COMMONSENSE -

Suppose you are in India. You have a friend in the US. It's your birthday today. He comes to your house today and wishes you a happy birthday. You are totally pleasantly surprised. You ask him, "Hey! How come you are in India this time? What made you come? When did you come?" He says, "I came for your birthday, to wish you in person". You won't believe that. You would laugh and say, "come on, jokes apart. What makes you come to India this time?" He says, "I treasure our friendship so much that it made me come from the US to India to wish you on your birthday". You will clearly not believe this.

Now, the question is - why wont you believe this? "Treasure friendship so highly => travelled a long distance for birthday" fits in logically. (It is not like saying "A is greater than B => A is less than B"). But is it "real"? No. It's not believable. This is commonsense. 

It is just like saying that a sentence might make sense grammatically, but may not not mean anything semantically. Logic is like grammar, commonsense is like semantics.

Additionally, if tomorrow someone gives you a brain-scan medical evidence that the friend actually meant that about treasuring the friendship so much, you would be lost and think he has a mental problem. That would be your inference. Because no regular friends would behave like this. This is 'reason'. Commonsense is 'reason', in the real world.

Also, this example belongs to a class which shows that commonsense is the 'laws of the mind' (how the friend should think). (Perhaps, every piece of commonsense, i.e. even otherwise, is a law of the mind).