Intuition

“The intuitive mind is a sacred gift and the rational mind is a faithful servant. We have created a society that honors the servant and has forgotten the gift.” - thus spoke Albert Einstein.

I find it quite strange that a scientist like him ever quoted that. May be we need to read it in the context of the overall conversation when he said that. Perhaps he was alluding to the importance of being imaginative.

The following simple examples show that following simple intuition does not always lead to truth and science teaches us to experiment and probe.

Sun 'rises' in the east and 'sets' in the west but Sun is not moving, rather it's earth which is moving! It seems trivial now but scientists had to fight hard to prove it to society.

Earth is round. However, wherever you go you see it is flat. You drive thousands of miles, still you see it as flat. Again, intuition tells us that it is flat but it is not.

Anyway, Einstein also said, "The important thing is not to stop questioning. Curiosity has its own reason for existing."

Need vs Want

We loosely know what they mean but always have hard time categorizing them. Copying from http://www.socialstudiesforkids.com/articles/economics/wantsandneeds1.htm 

A need is something you have to have, something you can't do without. A good example is food. If you don't eat, you won't survive for long.

A want is something you would like to have. It is not absolutely necessary, but it would be a good thing to have. A good example is music. Now, some people might argue that music is a need because they think they can't do without it. But you don't need music to survive. You do need to eat.

I have tried to put the above concept in a diagram and classified the red quadrants as type I & type II errors. Basically, you probably should not want 'things' that you don't need(Type II error) and also not say that you don't want 'something' even though you actually need it (Type I error, actually harder to identify). 

Quality x Quantity = Constant