How does one define love?
Different traditions have come at the question from varying angles.
Hippies, for example, see love as a lifestyle, a practice. People participate in love, whether sexual or platonic. They give themselves to the movement. Love is a noun.
Christians see love more in terms of an action than a feeling. One doesn't "fall" in love, one loves. What is love? Laying down your life for friends. Christians love through performance---there is disobedient love (adultery) and obedient love (fidelity). Love is a verb.
These are two camps among many. Woody Allen's art doesn't necessarily fit into either. His vision of love is simply that the heart is a strange place. In a Time magazine interview he famously quipped, "The heart wants what it wants. There's no logic to those things. You meet someone and you fall in love and that's that." Love is a muse.
The aforementioned article arose it the early stages of his romance with Soon-Yi Previn---now his wife, but at the time she was the adopted daughter (Andre Previn is her father) of his former girlfriend, Mia Farrow. Many saw his "the heart wants what it wants" plea as a guilty man's ploy to obfuscate matters, an attempt to slyly tip toe around the moral questions raised by Mia Farrow regarding his relationship with Soon-Yi.
Allen has always been careful to distinguish between reality and fiction, between his art and his life. Some readers still doubt this, but he did not grow up in a house under a roller coaster on Coney Island. Still, the circumstances of his relationship with Soon-Yi seemed too close a merger between art and reality. What critics applaud in two dimensions they ridicule in three.
A central theme in Allen's art is the unpredictability of love. This theme is there from the start, whether you're looking at Everything You Always Wanted to Know About Sex But Were Afraid to Ask or The Whore of Mensa or The Shallowest Man. This is the theme that caused audiences to fall in love with Annie Hall, Manhattan, and Hannah and Her Sisters. It remains an undercurrent in recent films Anything Else and Vicky Cristina Barcelona.
Ironically, it's this recurrent theme concerning the unpredictability of love that have caused many to love the art while disapproving of the artist.
Allen's movies showcase the unpredictability of love in two salient ways. First, love can arise out of unexpected or unlikely circumstances. Second, the heart is surprising in what it desires. It might stand on its toes for a girl with whom one might discuss Melville or go ga-ga for a girl whose absolutely destined to cheat. "You meet someone and you fall in love and that's that."
Of Allen's preeminent themes, this is perhaps the most common. If you're new to his work, you'll have to grapple with these ideas. What is the nature of love and where are its boundaries? Whether one accepts or profoundly disagrees with Allen, few contemporary artist frame the question so beautifully, or know it so intimately.