"Dream" come true

My secondary friend, Kim Kiat is a high self confident person and he always told me that:

"If you think you can, You can." or "Nothing is impossible"

He said that if you feel that you are so confident of doing something, impossible will become possible, because nothing is impossible!

I know that it is all just his Cognitive Thinking - Self Fulfilling Prophecy. He got an expectation about the occurrence of the thing in fact. He do believe what he think, might be truth and he can handle it when he believe he can.

Just want to let him know, if good to have confident to something else; but not over confident because it will just make your life go worst.