Sentence:  A base, <WSD>low-hearted</WSD> wretch, as you justly call him, with all his pride of ancestry; and more an enemy to himself with regard to his present and future happiness, than to you, in the barbarous and ungrateful wrongs he has done you; 
Meaning of the word marked with <WSD> tags:  Morally reprehensible, cowardly, or untrustworthy.