[opinion=mine]
"In Love" = Infatuation, Limerence, or "Puppy Love" caused by flood of endorphins in the brain.
"Love" = The reciprocated giving of comfort, devotion, familiarity, honor, mercy, respect, sacrifice, and trust.
"Lust" = Surge or spike in reproductive hormones in the body.
[/opinion]
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The mere fact that science may not yet adequately explain an object, event, or experience does not mean the immediate explanation should automatically default to a conspiratorial, extraterrestrial, paranormal, or supernatural cause.