An article in The Wall Street Journal tried to explain that real love doesn't come from God; instead, love is just a bunch of chemical reactions in your brain. According to the article:

Valentine's Day is here so get ready to send and receive heart-shaped chocolates and cards decorated with big red hearts. But wait a minute! Not so fast. Neuroscience has discovered that the heart has very little to do with romance. For accuracy you should send your main squeeze a Valentine's Day card with the image of a squishy gray blob evocative of a rotting cauliflower—the brain—because that's where romance really resides. And instead of saying "I love you," the knowledgeable lover would say, "Darling, dopamine floods my caudate nucleus" every time I look at you. Love and attraction are all tangled in the convoluted wiring of the brain.

So what is love? Neuroscience tells us that love is a condition involving neurons, neurotransmitters, hormones, receptors, and circuits in your brain. Cognitive science defines passionate love as an "elevated activity in the brain pathways which cause feelings of euphoria, strong motivation, and heightened energy which can induce sleeplessness, loss of appetite, and obsessive thinking about the beloved."

Possible Preaching Angles: God's love; Human love—Of course this illustration reflects a woefully inadequate view of love. The human mind cannot describe and explain either what love is or how it works.