
Left: a depiction of Cupid hitting a wall, possibly iconic of love ending, in a 2011 article on the down and outs of Valentine ’s Day. [2] Right: a depiction of Cupid and his arrow bring about marriage, on the back cover of American electrochemical engineer Libb Thims' 2007 textbook Human Chemistry. [1]

In mythology, Cupid is the iconic representation of love and or desire, the process of love, falling in love, or the chemistry, in general, that brings about love, typically depicted as a winged cherub holding a magical bow and arrow, a shot from which makes a person fall in love.

History
In the Middle Ages, the Greco-Roman story of Cupid and Psyche evolved into the myth of Cupid carrying two sets of arrows: one set gold-headed, which inspire love; and the other lead-headed, which inspire hatred.

Modern cupid
In modern terms, following the publication of German polymath Johann Goethe's 1809 Elective Affinities, the myth of Cupid's arrow bring about love, has been replaced by the measure of change of Gibbs free energy pre-determining love, which amounts to love and hate being explained not in terms of two sets of arrows, gold and lead, but rather by two sets of reaction tendencies or drives: negative free energy change (engendering love) and positive free energy change (dis-engendering love). [1]

References
1. (a) Thims, Libb. (2007). Human Chemistry (Volume One). Morrisville, NC: LuLu.
(b) Thims, Libb. (2007). Human Chemistry (Volume Two). Morrisville, NC: LuLu.
2. Squeeze, Jane. (2011). “Hump Days: Cupid’s Stupid; Love isn’t”, 303 Magazine, Feb 08.

Further reading
● Sternberg, Robert J. (1998). Cupid’s Arrow: the Course of Love through Time. New York: Cambridge University Press.

External links
● Cupid – Wikipedia.