Dhara Gupta lived all her life in a village near Jaisalmer in the Rajastan desert. One day, in 1822, as she was cooking dinner, she became aware of a commotion. She looked up to discover that her cousin, Mahavir, had returned from a trip he had begun two years before. He looked in good health, and over dinner he told them of his adventures.
There were tales of robbers, wild animals, great mountains and other incredible sights and adventures. But what really stunned Dhara was his claim to have seen something called ‘ice’.
‘I went to regions where it was so cold, the water stopped flowing and formed a solid, translucent block,’ said Mahavir. ‘What is more amazing is that there is no state in between where the liquid thickens. The water that flows freely is only slightly warmer than that which has solidified.’
Dhara did not want to challenge her cousin in public, but she did not believe him. What he said contradicted all her experience. She did not believe it when travellers told her of fire-breathing dragons. Nor would she believe this nonsense about ice. She rightly thought she was too intelligent for that.
Source: Chapter X ‘On Miracles’ from An Essay Concerning Human Understanding by David Hume (1748)
How could Dhara be right when in one sense she was so obviously wrong? We know that Mahavir’s account of ice was not a fantasy on a par with tales of dragons, but an accurate description of what happens to water at freezing point.
Dhara was right in the sense that sometimes we are wrong for the right reasons. Take, for example, get-rich-quick schemes. Most people who use email will receive messages virtually every day promising huge riches for a ‘small’ capital outlay. Because these are almost without exception frauds and it would take too much time to investigate their credentials one by one, the only rational course of action is to ignore them all. However, that means it is possible that one day you will ignore a genuine opportunity and forgo great wealth. That particular email would not be a fraud, yet in an important sense you would still have reasoned correctly when you concluded it probably was.
The same general point applies to Dhara. We should not believe everything we are told about how the natural world works. When people tell us that they can levitate, stop watches with their minds or cure diseases with crystals we should rightly be sceptical. Our past experience tells us that such events do not happen, and all previous claims that they have occurred have either lacked evidence to back them up or been shown to be fraudulent. We do not need to think that those making the claims are themselves con artists: they may simply be mistaken or basing their claims on bad reasoning.
The problem is, however, that sometimes something genuinely does come along that forces us to reconsider what we thought we knew. We cannot dismiss an idea simply because it doesn’t fit with our present beliefs. Rather, we need very good reasons to do so, because what is firm and established has to carry more weight than what is being claimed by an individual or small group which goes against it.
This is where Dhara has a problem. The testimony of one person, even if it is her cousin, is not strong enough to contradict what she knows about the natural world, where liquids do not change to solids at a seemingly magical temperature. Yet she must also accept that she has not been to these colder climes, whereas her cousin has. Her own experience is therefore limited, but she has only her cousin’s word about what lies beyond it. By refusing to believe him, did she make the limits of her knowledge too narrow, or was being wrong on this occasion the price she paid for not being gullible and mistaken in many more situations?
See also
| 40. | The rocking-horse winner |
| 63. | No know |
| 76. | Net head |
| 97. | Moral luck |