Thomas Moore, in his book Soul Mates describes a soul mate as someone to whom we feel profoundly connected, as though the the communication and the communicating that takes places between us were not the product of intentional effort, but rather a divine grace. Richard Bach describes the relationship as, “our soulmate is one who makes life come to life,” and portrays the partner as “one who unveils the best part of the other.” 

So ancient is the desire of one another which is implanted in us, people would spend their lives looking for their other half—their soul mate. For many, this search for their true love is the most important thing in their lives. This is exemplified throughout both ancient and modern literature.

The ancient Greeks used to host philosophical get-togethers attended by some of the most renowned thought-leaders in history. One of the most infamous discussions, The Symposium, was transcribed in great detail by the prolific philosopher Plato, who moderated the night’s discussion on the nature, purpose, and evolution of love. The attendees were each required to take the floor to describe their thoughts on the emotionally complex topic.

Plato’s Symposium, depiction by Anselm Feuerbach

The fourth speaker of the night, Aristophanes, was said to have painted quite a dramatic picture of the reason people so passionately seek a mate. His theory was that primitive humans were descendants from the moon and were androgynous—half male, half female. These sexually ambiguous beings set out to climb to the heavens to be one with the gods.

Aristophanes describes the fateful event:

Terrible was their might and strength, and the thoughts of their hearts were great, and they made an attack upon the gods; attempted to scale heaven, and would have laid hands upon the gods. Doubt reigned in the celestial councils. Should they kill them and annihilate the race with thunderbolts, as they had done the giants, then there would be an end of the sacrifices and worship which men offered to them; but, on the other hand, the gods could not suffer their insolence to be unrestrained. At last, after a good deal of reflection, Zeus discovered a way.

He said: ‘Methinks I have a plan which will enfeeble their strength and so extinguish their turbulence; men shall continue to exist, but I will cut them in two and then they will be diminished in strength and increased in numbers; this will have the advantage of making them more profitable to us. They shall walk upright on two legs, and if they continue insolent and will not be quiet, I will split them again and they shall hop about on a single leg.

As punishment, Zeus, the god of all gods, chopped each person in half, separating the bodies into two separate beings.

After the division the two parts of man, each desiring his other half, came together, and throwing their arms about one another, entwined in mutual embraces, longing to grow into one, they began to die from hunger and self-neglect, because they did not like to do anything apart; and when one of the halves died and the other survived, the survivor sought another mate, man or woman as we call them,–being the sections of entire men or women,–and clung to that.

Aristophanes concludes his thesis on why we love each other:

Suppose Hephaestus (Greek God of welding and sculpturing), with his instruments, to come to the pair who are lying side by side and to say to them, ‘What do you mortals want of one another?’
They would be unable to explain. And suppose further, that when he saw their perplexity he said: ‘Do you desire to be wholly one; always day and night in one another’s company? for if this is what you desire, I am ready to melt and fuse you together, so that being two you shall become one, and while you live a common life as if you were a single man, and after your death in the world below still be one departed soul, instead of two–I ask whether this is what you lovingly desire and whether you are satisfied to attain this?’–

There is not a man of them who when he heard the proposal would deny or would not acknowledge that this meeting and melting into one another, this becoming one instead of two, was the very expression of his ancient need. And the reason is that human nature was originally one and we were a whole, and the desire and pursuit of the whole is called love.

While the tale may be a quixotic interpretation of mutual attraction, it shows that love, in all its glory and despair, has captured our imaginations and dominated our conversations since time immemorial.

For many people, love is the most important thing in their lives. This is exemplified throughout both ancient and modern literature. In his book, The Psychology of Love, American psychologist Robert Sternberg explains, “Without it, people feel as though their lives are incomplete.” Similarly, “Faith, hope, and love abide, these three; but the greatest of these is love,” says Saint Paul in a letter defining love to the Corinthians. He goes on to say, “Love bears all things, believes all things, hopes all things, endures all things.” Additionally, the poet Robert Frost expresses, “Love is an irresistible desire to be irresistibly desired.”

While spiritual gurus proclaim that love is the ultimate ground of all life, some philosophers and literary masters are unsympathetic in their expression of the sentiment: “Love is a serious mental disease,” says Plato. The author Oscar Wild calls love an “illusion.” John Dryden, an influential British poet, describes love as a “malady without a cure.”

What is this love that captivates the imaginations of so many—sages, prophets, philosophers, scientists, and you and me alike? Is love merely a physiological response that is born somewhere in our brains, or is it something more, something deeper and enduring?

To love and be loved is a fundamental and involuntary yearning. Our day-to-day connotation of love embodies a deeply passionate yet enigmatic feeling toward another person. Hippocrates proposed in 450 B.C. that emotions emanate from the brain and, since the dawn of scientific inquiry, researches have feverishly searched for the “seat” of love within the human brain. The science of biology describes love, matter-of-factly, as an emotion of evolutionary significance, a result of chemicals transmitting across neurons.

But despite our obsession with this lure—and the affection, passion, and rejection that often accompanies it—scholars and scientists struggle to this day to define what love is and who a soul mate is.