According to Wikipedia, polyamory is the practice of, or desire for, intimate relationships with more than one partner, with the consent of all partners involved. Here is how I would re-define this:
Polyamory is realizing you have an infinite capacity to love and allowing yourself to develop feelings for multiple people in your life in an ethical way.
When I had my second child I realized my love for the first child had not diminished at all. And if I ever have more children, I'm sure that the love for my first two will not suffer. I still have feelings for my exes that I dated before I met my husband. Maybe those feelings are no longer romantic, but they are still tender and beautiful, and are to me simply a different kind of love. I have a few close friends that I love dearly, and when I develop friendships with new people I meet I still love my existing friends. Sometimes I meet people that are not my friends or family that I genuinely like or even love. I believe that I have an unlimited capacity to love and that connecting with people is the most interesting, fulfilling, and beautiful experience one can have.
I love getting to know new people and learning how they think. I love getting new perspective on life from people that come from different backgrounds and cultures. I love people.
Why is it okay to have many friends but not okay to have many partners? Why do we, as a society, think that one person can meet all of our romantic needs? That just does not make any sense to me. If we applied this logic to friendships, we would only need one friend that we'd do everything with. The tricky part would be to find someone who is into exactly the same set of hobbies as you, who likes doing things you like doing at the same time you do, who wants to have chinese for dinner when you do, and who would pretty much meet all of your personal needs. But that's not how it works. I have friends that I go to play tennis with and others that I take yoga classes with and some friends I go to for financial advice, while others are great as cooking partners...
My husband has a very special place in my heart and in my life, he is my rock and my partner in crime and my best friend. But do I really think he can meet all of my romantic/spiritual/emotional needs and give me a variety of new perspectives on life as if he comes from multiple backgrounds? Of course not. Why do we limit ourselves to having only one partner and think that "till death" they will be able to match exactly what we need romantically and as life partners? If only we allow ourselves to feel what we feel and stop being afraid of what others might think, our lives could become so much more fulfilling and interesting...
Am I saying that everyone is polyamorous? No. Some people are perfectly fine with only one partner for life. However, what I notice more and more among my friends and acquaintances that get married is an eventually (an inevitable) attraction to someone else, resulting in either infidelity or an extremely unhealthy suppression of emotion.
Polyamory has allowed me to explore sides of myself I didn't know were there. And, in turn, this digital exploration is meant to be more of an urge for self-analysis, for myself and for you, rather than a persuasion piece for the world of polyamory. Speak to your partners, urge them to open up, and don't be afraid to discover the possibilities that lie there.