The King in Kalidasa’s Shakuntala is a stranger to Shakuntala – his first view of her even stresses the fact that he is used to urban girls while Shakuntala is from the forest. In the immortal love legend from medieval India, Heer and Ranjha are strangers who meet only because Heer is forced to leave his own village. In Shakespeare’s Romeo and Juliet, Romeo asks his servant on first seeing Juliet, “What lady is that…?” – to which even the servant replies, “I know not, sir.”

In the 1957 romance classic, An Affair to Remember, Nicky and Terry (Deborah Kerr and Cary Grant) are strangers, even engaged to other people, who meet on a cruise. The list is long: love seems to blossom between strangers in most legends and stories across ages and cultures.

This is apparently very different from a common political discourse, which blames strangers for almost all the evils one can think of. In rich Europe, “migrants” are supposed to be hollowing out their “welfare” funds, while in rich USA immigrants are out after American jobs. Shia and Sunni leaders exchange blame (and more) over most of the Muddle East.

India has its own discourses about the danger of strangers: Hindus vs Muslims, of course, but also the way in which some rich families in places like Delhi seem to fear poor, working class strangers from places like Bihar. Politicians in all countries reap rich dividends by frightening people with the bogey of strangers, real or constructed.

In some ways, this dichotomy is at the core of my new study, The New Xenophobia: the stranger who is the source and target of love in almost all our great love stories is often made the target of hatred and the source of fear in many of our political narratives. Why is this so? Why this huge difference between two sets of narratives?

As the great twentieth century (Jewish) philosopher, Emmanuel Levinas – who himself experienced the hatred that European Nazis directed at “strangers” like European Jews – put it: of course, the stranger can pose or seem to pose a threat, but the stranger is also possibility, responsibility and a beginning.

The stranger brings us face to face with our own vulnerability as human beings. Suddenly, as Levinas notes, we are faced with the fact that we are not alone to act in this world. We can push a stone, we can uproot a tree, but the other – or the stranger – is not subservient to our will.

The other – or stranger – has a will of her own. Faced with this other will, which can coincide with our will or clash with it, we are faced with the realisation that human beings are never alone to act in the world. All violence, Levinas says, arises from a refusal to accept this fact: violence is when we act as if we are alone to act.

Hence, the stranger can present us with an obstruction, and it can be easy to want to hate – and kill – the stranger. But in doing so, we make ourselves blind to the possibilities that the stranger also offers: love is one possibility. It seems to be our choice: are we going to make ourselves insular and deceptively invulnerable by seeking to destroy, or are we willing to share our vulnerability with the stranger?

Because that is what love is: Love means becoming vulnerable to someone else, someone who is always, to some degree, a stranger. When we are in love, the wellbeing or happiness of the beloved comes to mean as much as – no, at times, more than – our own wellbeing and happiness. We make ourselves vulnerable to the other, and in that we face up to the fact that vulnerability is an aspect of life. Political discourse of the sort that blames strangers for all our ills tries to fool us into believing that we can become invulnerable. It makes us cheat ourselves. It promises us a life that cannot exist.

Perhaps that is why all kinds of xenophobia finally lead to acts of murder, destruction and oppression, not to the celebration of life.

Tabish Khair is a poet, novelist and teacher. He is the author of The New Xenophobia.