Wow, McGrath...a duty to deceive...this boggles me, and I am expanding my mind just trying to get my mental arms around it. I have been jejeune and naive in many ways in my life, in spite of many adventures to strange places, and I don't think I have ever encountered a situation where I felt directly I had a duty to deceive, except where I believed I was dealing with someone who was already busy being an enemy to me. Hard to say.I remember a bosn coming up to me one time with the idea of lifting some lumber he thought he could use from a large pile of it stored on the quay....and I told him I wished he'd never asked me, because then I had to say no. But that was a sort of practical hypocrisy, no duty there.
I guess I could see it plainly if there was no better way, in dealing with enemies or protecting the weak, or ill, in very peculiar circumstances...at least I could imaghine it.
When, then, have you really had such a duty, or known someone to...I am just curious to understand it better...