Final answer:
In 'The Alchemist,' Santiago is the character that best portrays the author's theme of pursuing one's personal legend. His journey symbolizes the necessity of following one's dreams and ambitions amidst various challenges, and his interactions with other characters highlight different facets of this pursuit.
Step-by-step explanation:
In Paulo Coelho's novel, The Alchemist, the character that best portrays the author's theme of the pursuit of one's personal legend would arguably be Santiago. This is because Santiago's journey embodies the core message of the book, which is about following your dreams and listening to your heart. As the protagonist, he leaves his comfortable life as a shepherd to search for a treasure by the pyramids in Egypt, a journey that symbolizes the pursuit of personal desires and aspirations. Along the way, Santiago encounters various characters that represent different aspects of this journey.
Melchizedek represents the guidance of spiritual figures in understanding and following one's personal legend, steering Santiago onto the path of his quest. Fatima epitomizes love and destiny, teaching Santiago that true love doesn't impede one's personal legend but rather complements it. The Crystal Merchant, on the other hand, illustrates the importance of pursuing dreams but also serves as a cautionary example of what happens when fear prevents a person from pursuing their dreams fully.
Thus, while other characters support and elucidate the theme, it is Santiago's character that actively engages with and embodies the author's theme throughout The Alchemist, making him the character that best portrays it. Santiago's quest, replete with challenges, symbolizes every individual's journey to fulfill their own personal legend.