Sentence:  It follows , then , provided the possibilities have been exhausted , that the only real alternative is the general viewpoint of the `` left '' , which has been represented on the Continent by Fritz Buri and , to some <WSD>extent</WSD> at least , is found in much that is significant in American and English theology . 
Meaning of the word marked with <WSD> tags:  the point or degree to which something extends