"Love is as universal as grief." Keystone/Getty Images

We spend our lives chasing it, nurturing it, or watching it slip away. Yet the truth about love seems to dissolve in the light, evading any attempt at definition. Are we any closer than the famously love-struck ancient Greeks to understanding what it is?
The definitions that work best are deliberately imprecise. Love is “kind of like when you see a fog in the morning… before the sun comes out” (Charles Bukowski); or “a bright stain on the vision, blotting out reason” (Robert Graves); or “the extremely difficult realisation that something other than oneself is real” (Iris Murdoch). A friend of mine, after considering the question, produced his favourite cookery book, from which he had entertained countless friends and family. Love is a different thing to each of us, and everything to all of us. It leaves us enormously vulnerable: we know what it is for sure when we lose it.
In recent years, neuroscientists have tried to explain love in terms of the brain chemicals that accompany it, which have a powerful influence on our behaviour. Is that sufficient? Can this thing that “looks not with the eyes, but with the mind”, as Shakespeare had it, really be understood as a neurological condition?
This question is at the heart of Lucy Prebble’s play The Effect. It tells the story of two young people who enrol in a clinical trial for a new antidepressant. During the trial they fall for each other and then worry whether what they’re feeling is real or merely “chemical”, a side-effect of the drug. Things get even more confusing when one of them learns she’s on a placebo, which convinces her that she can’t possibly be feeling for her lover what he feels for her. If love is a drug, can a drug lead to love? Not while you’re still on it, she seems to be saying.
The Effect is fraught with existential angst about the nature of emotional health and how we interpret what we feel. We learn, for example, that the clinical psychiatrist who is running the trial suffers from long-term depression, a condition she has chosen never to be treated for: she believes that the drugs don’t work, and in line with a particular strand of philosophical thinking views the illness as a grand existential tragedy or the natural state of things. The central conundrum — is love authentic if it’s manipulated by chemicals? — is never fully answered, though the ending gives us pause when the protagonists walk off hand-in-hand and drug-free into their uncertain futures looking a lot more loving than they did at any time during their chemical romance.
At a certain level, love is all about chemistry. Neuroscientists have found that different kinds of love are associated with different hormones and neurotransmitters. Sexual desire is driven by testosterone, whose main purpose seems to be to encourage us to have sex with as many partners as possible. Romantic love, that giddy, obsessive state designed to win us the affections of a particular partner, is the brain’s dopamine reward system on overdrive — a hit for every Whatsapp message returned, every infatuated thought of the beloved. Meanwhile, those warm feelings of security and connection characteristic of long-term attachment are marked by increased levels of vasopressin and oxytocin.
Join the discussion
Join like minded readers that support our journalism by becoming a paid subscriber
To join the discussion in the comments, become a paid subscriber.
Join like minded readers that support our journalism, read unlimited articles and enjoy other subscriber-only benefits.
Subscribe