PVL3702
Assignment 1
Semester 1
Due March 2026
, Mistake as to the Nature of the Subject Matter (Error in Substantia) and the
Validity of the Contract
1. Introduction
In South African contract law, a mistake may affect the validity of a contract where the
mistake relates to a material aspect of the agreement. In the present scenario, both
Jabu and Raymond concluded a contract on the common assumption that the ring was
a genuine diamond ring. It later emerged that the ring was in fact fake and made from
artificial materials. The relevant legal issue is therefore the type of mistake involved and
whether such mistake renders the contract valid or void.
The discussion below focuses on the doctrine of mistake, particularly error in substantia
(mistake as to the nature or quality of the subject matter), with reference to relevant
case law. Latent defects, breach of contract, and the Consumer Protection Act 68 of
2008 are excluded as required.
2. Nature of the Relevant Mistake
The mistake in this case relates to the quality and identity of the subject matter of the
contract. Both parties believed they were contracting for a genuine diamond ring, but
the item was in fact not a diamond at all. This constitutes a mistake as to the substance
or essential qualities of the thing sold, known as error in substantia (Hutchison &
Pretorius, 2017).
Error in substantia occurs where a party is mistaken about the nature, quality, or
attributes of the subject matter, and such attributes are essential to the agreement. If
the mistake is material and relates to a fundamental element of the contract, it may
prevent true consensus from being formed (Christie & Bradfield, 2016).
In this scenario, the genuineness of the diamond is clearly an essential attribute of the
ring. Raymond offered R80 000 specifically because he believed he was purchasing a
Assignment 1
Semester 1
Due March 2026
, Mistake as to the Nature of the Subject Matter (Error in Substantia) and the
Validity of the Contract
1. Introduction
In South African contract law, a mistake may affect the validity of a contract where the
mistake relates to a material aspect of the agreement. In the present scenario, both
Jabu and Raymond concluded a contract on the common assumption that the ring was
a genuine diamond ring. It later emerged that the ring was in fact fake and made from
artificial materials. The relevant legal issue is therefore the type of mistake involved and
whether such mistake renders the contract valid or void.
The discussion below focuses on the doctrine of mistake, particularly error in substantia
(mistake as to the nature or quality of the subject matter), with reference to relevant
case law. Latent defects, breach of contract, and the Consumer Protection Act 68 of
2008 are excluded as required.
2. Nature of the Relevant Mistake
The mistake in this case relates to the quality and identity of the subject matter of the
contract. Both parties believed they were contracting for a genuine diamond ring, but
the item was in fact not a diamond at all. This constitutes a mistake as to the substance
or essential qualities of the thing sold, known as error in substantia (Hutchison &
Pretorius, 2017).
Error in substantia occurs where a party is mistaken about the nature, quality, or
attributes of the subject matter, and such attributes are essential to the agreement. If
the mistake is material and relates to a fundamental element of the contract, it may
prevent true consensus from being formed (Christie & Bradfield, 2016).
In this scenario, the genuineness of the diamond is clearly an essential attribute of the
ring. Raymond offered R80 000 specifically because he believed he was purchasing a
