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What did Robert Gascoyne-Cecil, 3rd Marquess of Salisbury, do as a member of Parliament?
Robert Gascoyne-Cecil, 3rd Marquess of Salisbury, opposed secular education and ultramontane interference with the Church of England which was at variance with the fundamental principles of our constitution.
What did Robert Gascoyne-Cecil, 3rd Marquess of Salisbury, say after saying he opposed secular education and ultramontane interference with the Church of England?
Robert Gascoyne-Cecil, 3rd Marquess of Salisbury, would oppose any such tampering with our representative system as shall disturb the reciprocal powers on which the stability of our constitution rests.
Did Robert Gascoyne-Cecil, 3rd Marquess of Salisbury, do anything notable while in Parliament?
Robert Gascoyne-Cecil, 3rd Marquess of Salisbury, opposed secular education and ultramontane interference with the Church of England which was at variance with the fundamental principles of our constitution.

Question: What was his reason for opposing this?
Self-contained rewrite: What was Robert Gascoyne-Cecil, 3rd Marquess of Salisbury's, reason for opposing this?