Why Heart is the symbol/sign of love!

Everybody knows what's the symbol of love, heart & sometimes an arrow pierced through it.

People are quite used to make  statements linking heart like 'use your mind instead of your heart while making a tough decision'. Though its meaning is clear -- choose the right path which may be tough to follow, but it sounds like ancient zen. So & so has a big heart represents generosity of the third person. 
But why heart, it could be anything. What about other parts of the body - kidney, lungs, belly etc.  They are not less important than heart w.r.t. the human body. This thought clicked in my mind some years ago. I did a Google search -"Why heart is the love symbol" & found 13 million sites so I'm not the first who had this thought.

Its more logically to say that 'I love you from my mind' then to say that 'I love you from my heart'. Saying  'I love you from my heart', is as reasonable as  saying that 'I love you from my thumb'. It doesn't make any difference.     
It could be brain more logically as our brain thinks, responds to love & affection & is responsible for all intellect & intelligence. Heart does nothing other than pumping blood & adjusting the blood flow in special events. When we face a snake or a bull charging toward us, our heart races & beats faster to adjust the blood flow as per the current needs. Heart beats fluctuates in other situations like when somebody confronts someone with whom he is emotionally attached like the situation of proposing someone. When someone hurts you emotionally, you feel a pain in the chest. Every such thing is chemical phenomenon & has no real relation with emotions. In my opinion first the emotions is felt by the brain & then the body including the heart responds to it. So the response of heart is just a byproduct of emotions instead, it is believed to be cause of emotions, that's entirely a myth. 

In ancient Egyptian civilization, people who built mighty pyramids used to believe that heart is responsible for intelligence instead of brain. Brain was believed to be an organ responsible for cooling the blood.

Many classical philosophers and scientists, including Aristotle, considered the heart the seat of thought, reason  or emotion, often rejecting the value of the brain.    

The shape of heart barely resembles the shape of actual human heart. The seed of the silphium plant, used in ancient times as a herbal contraceptive, has been suggested as the source of the heart symbol. The plant has gone extinct. The blood red colored heart is a symbol of passion & strong emotion in European traditional arts. The hearts have constituted, since the 15th century, one of the red suits in most playing card decks. The symbol is common in Valentines day cards & other cultural artifacts representing love & affection.     

So, after some reading pertaining to the topic, I have reached to the conclusion that the symbol is regarded as the love symbol as a result of  ancient myths & philosphy. The symbol is heavily publicized in the medieval & modern periods of human civilization. It's entirely a western concept which is adopted by eastern cultures.

I used to wonder, whats the meaning of Heart pierced by an arrow. Here is the answer. Its the arrow shot by Cupid (Roman God of Love), causing the person to fall passionately in love. And it explains the pain and pleasure of Love & the deep wound or scar that Love leaves behind.........


Further readings ---
http://en.wikipedia.org/wiki/Heart_%28symbol%29
http://hubpages.com/hub/Loveandheartsymbol
http://www.answerbag.com/q_view/1040736