Sentence check

Hello!

Please help me with the following sentences:

1. Occultism is the belief in various theories, practices and rituals connected with magic powers and things that cannot be explained by reason or science.

(do we say: “explain by reason”?)

2. (it’s about Occultists)They believe that they can use knowledge of the occult to predict the future, effect healing.. (is “knowledge of the occult” correct ?

3. Devotees of the occult rejected modern Western values, and based their way of life on spiritual ideas and beliefs (can we say “based their way of life” or is it just used in sentences like “this story is/was based on....”

4.In France, for example, about 60 per cent of the people believe in magic. (shouldn’t it be: “of people”?'

5. Although, in most cases, the "possessed" are those in need of psychological therapy more than exorcism, the priests are glad that it is they who can offer the help, and not the fortune-tellers (shouldn’t it be: “that it is them, who” and “who can offer help”?)

Thank you