Yes is it very hostile. I only got through the first part.
I can sympathize and agree with him if he is attacking "tranquilism" if he interprets it as running from pain, but I gather that his deeper disagreement is his preference for "reason" over feeling:
To discover substance, then, is a great step in the life of reason, even if substance be conceived quite negatively as a term that serves merely to mark, by contrast, the unsubstantiality, the vanity, of all particular moments and things.