I mentioned in earlier posts that two major problems with the traditional (and all non traditional definitions ASAIK) of lying are problematic when it comes to cases of equivocation and implicature. My intuition strongly tells me that equivocations are lies when they are told with the intent to deceive but I am not so sure about implicature. My intuitions does not seem to be against implicatures with the intent to deceive as being lies. It may be a case by case thing with some cases being more intuitively lies than others.
There seems to be a way to get past the problems with a slight tweak of the definition. One can define lying (a modification of the traditional definition) thus:
X lies iff X expects (or believes) his interlocuter Y to interpret X's expression "P" to be expressing a proposition which X does not actually believe (or believes to be false) and for the purpose of deceiving Y into believing that P.
This definition may be adapted mutatis mutandis to other definitions of lies such as Fallis' which does not have a deception criterion but replaces it with a (intentional) violation of a Gricean linguistic norm to speak truthfully.
Under my definition, both equivocation and implicature are classified as lies. Why? The difference is in the reflective and psychologically transparent nature of the definition because it reflects what someone expects his interlocuter to be interpreting what he said.
To see this definition in action, here is a scenario involving equivocation.
John owes Jill $800 and has no intention to pay her back. Ever. He also has no cash on him now but has enough in his bank account to pay her. Jill sees John walking down the street and asks to be remunerated for the loan. John says "I have no money on me, but I will go to the bank". Jill agrees to wait for him. Instead of going to The People's Bank of Kentucky, John's bank (qua financial institution), John goes sun-bathing by the river bank and thus reneges on his obligations to pay Jill back once again.
Has John lied? Yes according to my definition. Under the traditional definition or the non traditional ones, it is indeterminate if John lied. Other definitions focus on what proposition was expressed which is ambiguous in the case of equivocation. But since John expected and intentionally made it so that Jill would interpret "bank" as John's financial institution and not some other meaning of that term for the purpose of deception, he lies. In other words, since John believes that Jill interprets "I will go to the bank" as the proposition I will go to my financial institution [presumably to get her money] (which John does not believe he will be doing) and not "I will go to the river bank" [to sunbathe] and for the purpose of deceiving her, he has lied.
Now take implicature. Consider our scenario above with a slight twist. John goes to his bank [financial institution] but instead of withdrawing money to pay Jill, he stands around the lounge for a bit and returns home. John implied that he is going to the bank to get money to pay Jill but what he said explicitly to her did not make mention of the rest. Under my definition, John is lying because he expects Jill to interpret what he says as "I will go to the bank to get the money to pay you back" and not as "I will go to the bank and do nothing but lounge around."
I thought of this definition when I remembered the reading of David Lewis's seminal book on linguistic conventions called "Convention: A Philosophical Study". In this work, Lewis uses the work done by the theoretical economist Thomas Schelling on focal point equilibria to solve for game theoretic "coordination problems" in socio-economic conventions. Lewis used it to analyse linguistic and other kinds of social conventions. In Lewis's work, he came up with the idea of "common knowledge" which employs the kind of reflective and psychologically transparent expectations and beliefs required for establishing linguistic/social conventions. His idea of common knowledge, however, has a theoretically possible indefinite number of iterations (I expect my interlocutor to expect that I expect that he expects that I expect and so on). Theoretically this could go on forever (and nothing will thus be accomplished) but rarely in actual socio-linguistic circumstances it goes beyond a few iterations. My definition stops at the second iteration. X expects or believes that his interlocuter Y believes X to be expressing some proposition P.
There may be cases where my definition draws the line too far and includes implicature scenarios as involving lies when they intuitively clearly should not be. I can't think of any off the top of my head but I suspect it so.
