Sentence:  If an evil which <WSD>is</WSD> certain and extensive and immediate may rarely be compensated for by a problematic , speculative , future good , by the same token not every present , certain , and immediate good ( or lesser evil ) that may have to be done will be outweighed by a problematic , speculative , and future evil . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)