Probably, I read this story in autobiography of M C Chagla, titled "Roses in December".
A custom dispute case was brought in his Court. A man has brought a pen made of Gold from abroad. The custom wanted to tax it as import of gold. The man claimed that it is not gold, it is pen and it is exampt from duty.
The Judge took the pen in his and hand asked Govt Counsel, "What is this?"... The Govt Counsel replied that "It is pen."
"That settles it", Judge said and closed case, dismissing claim of the Custom.
The point is : Judges solve many cases by asking common sense questions.
Haresh Raichura 18/11/16