I think it is a matter that, honestly, if I've experienced them being extremely frank with me about truly significant and difficult matters, willing to confront me if necessary, I doubt that they are going to bother to lie about little things like whether they like a movie I like. Can I know for sure? No. But do I spend any time at all worrying about whether everything that comes out of their mouth is completely real? No. The bottom line is that in matters that truly matter in my therapy, my therapists have been forthright with me and have done so with a consistency that makes is a pretty safe bet that they are being as real as any real person would be.