Housefull Economics

The Fallacy of Billa 786

Our weekly explainer on economics using lessons from popular culture. In Installment 31, Amitabh Bachchan enters a Spurious Relationship.

Billa 786 is a big deal for Vijay (played by Amitabh Bachchan) in Deewar. It saves his life when a bullet meant for him strikes the badge instead, and he subsequently treats it like a good-luck charm. He believes nothing can happen to him as long as the badge is with him. When he loses it, at the climax, something bad does indeed happen to him. (I’m trying to avoid spoilers here, though that may not be necessary for such an iconic film.) There is, however, no such thing as a good-luck charm. Vijay had fallen for a Spurious Relationship.

A Spurious Relationship is defined as “a mathematical relationship in which two or more events or variables are not causally related to each other, yet it may be wrongly inferred that they are, due to either coincidence or the presence of a certain third, unseen factor.” In this case, Vijay attributed his good fortune to the presence of the billa; and the film implied that when he lost the billa, he lost his good fortune as well. This was a Spurious Relationship. It was just coincidence (or ittefaaq, as he himself describes it while talking about the first incident) that the Billa saved his life.

There are many names for this fallacy of mistaking correlation for causation, such as Illusory Correlation and Post Hoc Ergo Propter Hoc. This is a natural fallacy for us to fall into, because humans make sense of the world by creating narratives as they search for meaning. All superstitions evolve from this, as do many conspiracy theories.

A recent example of this is poor Anushka Sharma. She got blamed for India’s defeat in the last World Cup, when her then-boyfriend Virat Kohli failed with the bat; and she got blamed again when India lost its first two Tests to South Africa. Poor Anushka had no more to do with those defeats than Arun Jaitley, who was finance minister during both those events.

An everyday example of this comes from Mumbai traffic. I was trapped in a jam yesterday at a particular bottleneck, and when we finally got past it, my companion in the car noticed that there was a traffic cop directing the traffic at the signal. “No wonder the traffic is so bad,” he remarked. “There’s a bloody cop directing it.” Neither of us knew, of course, which way the causation ran. Maybe the traffic became bad because the cop took over. Maybe the cop was forced to take over because the traffic got bad, and he was actually making it better. Maybe the traffic was going to be bad regardless of the cop being there, and this was inadvertent theatre. Traffic is complex — and so is the world.

Economists and politicians often make arguments that involve Spurious Relationships. Narendra Modi recently claimed credit for creating 7 million jobs during his tenure. This is a dubious claim. (I would argue that Demonetisation and GST actually lost many jobs, especially in the informal sector.) But leaving that aside, even if X number of jobs were created in his tenure, we do not know the counterfactuals (how many jobs would have been created under another administration), and there is no causation involved. Since India became independent, our society has achieved whatever it has in spite of the government, not because of it. So Modi taking credit for the jobs created since 2014 is much of a Spurious Relationship as the UPA taking credit for the growth in mobile-phone penetration in the years that Manmohan Singh was prime minister.

A writer named Tyler Vigen has actually written a book called Spurious Correlations, and his website has some lovely examples, a couple of which I’ve reproduced below. Those charts are convincing, aren’t they?

So let me end this piece by asking a question: readers of Pragati tend to be smarter than readers of other publications. Which way do you think the causation goes? 🙂


About the author

Amit Varma

Amit Varma is a writer based in Mumbai. A journalist for a decade-and-a-half, he won the Bastiat Prize for Journalism in 2007 and 2015. He writes the blog India Uncut, and hosts the podcast, The Seen and the Unseen. He is the editor of Pragati.