Final answer:
Jack Worthing's character in 'The Importance of Being Earnest' is introduced and developed through Cecily's affection and Miss Prism's admiration for his sense of duty.
Step-by-step explanation:
The character of Jack Worthing in Oscar Wilde's 'The Importance of Being Earnest' is introduced and developed through discussions between Miss Prism and Cecily which highlight different aspects of his personality. Cecily regards Jack with affectionate concern for his health and welfare, calling him 'Dear Uncle Jack', which underscores his familial importance and perhaps his reliability and consistency. In contrast, Miss Prism emphasizes Jack's sense of duty, especially concerning his care for his troublesome brother, displaying Jack's character as responsible and morally upright. These conversations reveal how Jack is perceived by different characters, contributing to the audience's overall understanding of his complex character.