>Although science cannot currently detect the 'soul' or 'spirit' as a material entity, it's interesting to remember that science has never been very kind to the things it cannot currently detect.

so such thing as soul. What can be implied without evidence can be dismissed without evidence. 

>Recall, for example, the Hungarian doctor, Ignaz Semmelwei (1846), who pioneered the discovery of 'germs'. His discovery was rejected by the scientific community; nobody would listen to him, and he was eventually committed to a mental asylum.1

false parallelism. 

>Given this definition, many psychedelic drugs have spiritual potential, if used ceremonially. This is because they give rise to the re-connection between mind and body; reveal trauma; and heal it. In other words, they can reconnect us to the "animating or vital principle held to give life to physical organisms."

no evidence. just make believe. 

>Psychedelics can heal, and the process is spiritual by the dictionary definition.

dictionary definitions don't heal.