Mortmain was a key underlying interdiction in legal history, contextualising much early case law. The decision of "Thornton v Howe" held that a trust for publishing the writings of Joanna Southcott was charitable, being for the "advancement of religion". This decision is often held up as setting the bar extremely low in determining whether a charity is for the advancement of religion. At the time of her trust-making the statutes against mortmain were in force and having not met the narrow, high-authority formalities for such a trust to be valid it was void, rather than imbuing it with special privileges in relation to taxation and viability. Identifying the trust within the general run of mortmain forbiddance shapes the case's "reasoning (ratio)".