> Ram Dass spends the first part of the book describing his journey. It involves a dive into the world of psychedelic drugs and their benefits and limitations. His experience essentially opens him up to Eastern mysticism.
There is some evidence that supports the notion that psychedelics increase openness to new ideas. This is the basis of psychedelic-assisted therapy, in which psychedelics are thought to make the patient more open to accepting the therapy intervention while unlearning their previously unhealthy thought patterns.
However, that openness to new ideas is a double-edged sword. People who use psychedelics in uncontrolled environments with excessive frequency can pick up a lot of strange ideas along the way.
Increasing one's openness to new ideas might be a good thing in the presence of a trained therapist or other well-meaning environments. However, it may become counterproductive in uncontrolled environments where users are prone to picking up conspiracy theories, new age mysticism, pseudoscience, or other misinformation that bombards us from all angles on modern social media.
Modern news article about psychedelics skew heavily toward the positives while burying the risks and downsides. For example, many people glorify Kary Mullis, inventor of PCR and 1993 noble prize winner, for his love of LSD. Few people know that he also believed he talked to a glowing raccoon in the forest, was a climate change denier, and didn't believe that HIV was related to AIDS. Being too open to new ideas is not unilaterally positive.