Love is an entirely baffling concept to most people. Most people, although they may have felt it, are at a complete loss when asked to describe it.
According to Grant Naylor "Love is a device invented by bank managers to make you overdrawn."
Medically and Scientifically speaking, Love and Lust are devices that benifit the "inevitable" offspring that you are about to produce with the person that you love. Lust drives you to mate, and Love drives you to stay with the person that you have mated with.
The evolutionary upshot of which is that a couple will stick together while their new-born infant is incapable of looking after itself.
The process by which the mind loves another is a complex chemicle coctail of endorphines that acts as a reward mechanism for spending time with your loved one or offspring. The reward mechanism fills the lovers with a profound sense of peace and loving. This will essentially become an addiction, which is understandable.
Religion and Love
Many a Christian will tell you that love only comes from the Bible, Jesus, and the soul. However, it is not all that difficult to partly explain love through biology, particularly evolutionary psychology.
There are essentially three kinds of love: love of family, romantic love, and friendship. The first deals ultimately comes from instinct to preserve genes. The second comes from procreation instincts. The third is essentially a social pact that confers survival advantages.
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But, doesn't this make love a mundane part of science?
Many will tell you that that isn't the case. The fact that we know how love works does not make it any less an excellent feeling.