Section 11 codifies the doctrine of res judicata ('a thing decided'), which prevents relitigation of the same issues between the same parties. Its five conditions are: (1) same matter directly and substantially in issue, (2) in a former suit, (3) between same parties or their privies, (4) litigating under the same title, (5) decided by a competent court. Section 10 deals with res sub-judice (pending suits), Section 9 with jurisdiction of civil courts, and Section 12 with bar on second suits.

1. 1 Pick up CPC.
2. 2 Check Section 9 → jurisdiction of civil courts. Not this.
3. 3 Check Section 10 → 'Res sub judice' (stay of suit). Close but not res judicata.
4. 4 Check Section 11 → 'Res Judicata.' ✓ Found it.
5. 5 Section 12 → bar on further suit. Not the definition.

The text reads: Section 11 CPC: No Court shall try any suit or issue in which the matter directly and substantially in issue has been directly and substantially in issue in a former suit between the same parties.