Feeling before thinking.

You cry because you are sad.
You tremble because you are afraid.
You smile because you are happy.

That’s what we think.
In reality, though, the truth is the other way around.

You are sad because you cry.
You are afraid because you tremble.
You are happy because you smile.

The brain is a system connected to the peripheral nerves
The body works through interaction with the environment.

The mind affects the action and vice versa; the action affects the mind (mood, emotion).

When you smile, that makes you happy.