Say the ratio out loud before you open Reasoning — recalling it unprompted is exactly what the exam pays for.
Why it matters
It states the reciprocity principle — the court recognises a jurisdiction which, with the necessary changes, it claims for itself. That single idea explains the recognition rules in two modules, and an answer that names it is doing more than reciting cases.
Facts
This course cites the case for the principle it underlies and does not set out its facts.
Held
A court recognises a jurisdiction which, mutatis mutandis, it claims for itself.
Reasoning
Step one — the principle is one of consistency. A forum that takes jurisdiction on a given connection cannot, without inconsistency, deny that the same connection makes a foreign court competent.
Step two — see it applied to adoption. In Re Valentine's Settlement the rule for recognising a foreign adoption is that the adoptive parents must be domiciled, and the child resident, in the country where the order was made — and this course says in terms that the rule was in line with the Travers v. Holley principle. Set it beside the English jurisdictional rule — applicant domiciled in England or Scotland, or applicant and infant resident there, with no domicile requirement for the child — and the two map exactly.
Step three — see it as the architecture of Module 2. Every ground on which a court takes jurisdiction is a ground on which it credits a foreign court with jurisdiction, and every ground it rejects for itself it rejects for the foreign court. Presence and submission for judgments in personam; power over the res for judgments in rem; competence in the international sense, never merely by the foreign State's own law.
Exam use
It opens: Why are foreign judgments and foreign status recognised on the grounds they are? — and it supplies the reason rather than the list.
Use it to compress two modules into one sentence. If you can state when an Indian court may hear a case, you can state when a foreign judgment will be recognised, because they are the same list read in opposite directions.
Then note the two places the symmetry is imperfect, because the examiner will reward the qualification. Nationality: Emmanuel v. Symon records that there is no direct English authority, and the accepted position is that nationality as such does not justify the foreign court's jurisdiction — consistently with the fact that English law does not claim it. Temporary presence: Carrick v. Hancock supports it, and the argument for it is precisely reciprocity, since English law itself founds jurisdiction on service during a fleeting visit; yet the course records that the point is not free from doubt, and that casual presence is undesirable where the cause of action arose elsewhere.
It does not decide anything about welfare or the merits in a custody case; reciprocity determines the forum, not the result.