Have you stopped beating your wife?

I'd just like to point out that there is a definite answer to this. If a person has never started beating his or her wife, then they cannot stop and the answer must be no. Is there a flaw in this reasoning? Or am I not using the common definitions?

Martin told Bob the building was on his left.

Here, too, I see a definite answer. The word "left" is possessed by the word "his." In the English language, the pronoun "his" (and similarly "him," "her," "it," etc.) always refers to the nearest possible preceding sensible noun. In this case, "building" is not a sensible word for "his" to refer to. The next nearest noun is "Bob," which does make sense for "'his" to refer to. Therefore, "his left" must refer to Bob's left. Of course, given context, the interpretation of "sensible" could change. If, say, Bob was giving Martin directions, and Bob just asked Martin to tell Bob what Martin saw (note that pronouns would more typically be used; I used names to allow a more certain answer upon careful reading), then "his left" would refer to Martin's left. Of course, this example is widely more open to interpretation, and I myself am not convinced.