It probably comes from reading too many fantasy novels and from playing Ultima IV during my formative years, but I somehow acquired a strong aversion to telling literal lies, to the point where I basically can't do it at all. On the other hand, using the truth with an intent to deceive feels fine; it doesn't trigger the same "OMG this is bad and wrong" emotional reaction I get when I think about lying outright to someone. It's like the restrictions on Aes Sedai in Robert Jordan's Wheel of Time series.

I also tell people this.