Sentence:  All this, laws, prejudices, acts, men, things, went and came above him, according to the complicated and mysterious movement that God impresses upon civilization, marching over him and crushing him with an indescribably tranquil cruelty and <WSD>inexorable</WSD> indifference. 
Meaning of the word marked with <WSD> tags:  Impossible to prevent or stop; inevitable. (from mid 16th c.)