Introduction:
In "The Third Level" from Class 12 English textbook, the writer wants to bring out the contrast between fantasy and reality through the experiences of the protagonist, Charley.

Fantasy:
Charley discovers a mysterious third level of Grand Central Station that transports him back to 1894. This fantasy world allows Charley to escape from the pressures of his present-day life and experience a simpler time.

Reality:
In reality, Charley's wife and doctor are worried about his mental health as he becomes increasingly obsessed with the third level. They believe that Charley is losing touch with reality and needs help.

Contrast:
The contrast between fantasy and reality is highlighted as Charley struggles to differentiate between the two worlds. While the third level offers him an escape, it also poses a threat to his mental well-being in the real world.

Symbolism:
The third level serves as a symbol of Charley's desire to escape from the complexities of modern life and find solace in a simpler time. However, it also symbolizes the dangers of losing oneself in fantasy and neglecting one's responsibilities.

Conclusion:
Through the contrast between fantasy and reality in "The Third Level," the writer explores the theme of escapism and the consequences of blurring the lines between the two worlds. Charley's journey serves as a cautionary tale about the importance of facing reality and accepting the challenges it presents.