'X' became symbolic for a kiss because in the middle ages when alot of people were illiterate and they used to sign documents with an X and then kiss it for sincerity.
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40% of people who are rejected in romantic love slip into clinical depression.
72
Approximately 141 million Valentine's Day cards are exchanged worldwide every year.
104
Couples' personalities converge over time to make partners more and more similar.
235
The left ear is more responsive to words of love and emotion whispered into it than the right.
44
Wearing red increases attraction.
30
When someone looks at a new love, the neural circuits that are usually associated with social judgment are suppressed.
130
In 2011, archaeologists discovered the skeletal remains of a Roman couple who have been holding hands for 1,500 years.
81