Date: Oct 7, 2013 11:01 PM
Author: Jonathan J. Crabtree
Subject: Was Brahmagupta Misquoted? "Debt multiplied by debt equals fortune"

Dear Friends

Many people quote Brahmagupta as saying 'debt multiplied by debt equals fortune'.

This is often in connection with -ve x -ve = +ve

I doubt Brahmagupta was that stupid!

Would you please help me locate verses 18.30-35 from the Brahmasphutasiddhanta and provide a trustworthy translation into English?

I have uploaded it to

NOTE: I have seen a translation by Colebrook, yet would prefer an expert run their eyes over the Sanskrit.

Thank you.

Yours sincerely,
Jonathan Crabtree
Mathematics Researcher
Melbourne Australia
(Currently over at

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