The quote "Always distrust your Mercedes from whom he is a single book reader" suggests a cautionary approach toward someone who is limited to just one source of knowledge or perspective, particularly in the context of a character named Mercedes in Arturo Pérez-Reverte's book "Alatriste." This highlights the idea that a narrow viewpoint can lead to misconceptions or a lack of depth in understanding.
In the narrative of "Alatriste," the emphasis on varied experiences and knowledge underscores the importance of diverse perspectives in forming well-rounded opinions. Trusting someone with limited knowledge may lead to misunderstandings or incomplete insights, pointing to the value of broadening one's horizons through varied reading and experiences.