What is a simple proof to the Butterfly theorem

I'm researching proofs to the Butterfly theorem and would like to see if I can find more :]
Please give a proof to the Butterfly theorem - in English (Give reasons to why this part is true and etc).

you can find it here:

http://mathworld.wolfram.com/ButterflyTh…

http://agutie.homestead.com/files/Geomet…

I think it means that everything has an impact on something down the road. For example, the theory posits that a butterfly flapping its wings produces wind that can affect something else. Basically, the theory is trying to convey the idea that everything we do in life can have a similar effect on out relationships, careers, ideas, etc.

Be as specific and detailed as you can. Use any personal experience or knowledge you might have.

You can use research to help support your answer.

http://tinypic.com/r/dfbm0m/5

Please download the file, i uploaded as image file, coz was unable to upload as doc. Tinypic dont allow .doc files

whats the base word to therom? theory aka not proven. thare is none

in english??? how else would i give it to you...? in chinese? ok. ching chong wing wang wong chong