Is disbelief in what you've been told by someone the same as calling that person a liar?

Well, in general, they aren't always the same. In your instance, that's probably how I'd take it. I'd also hazard a guess that there's more issues than what you're relaying (or even know about). I find it weird that they think it's a microphone, regardless of looks. If they think that's a reality, then there's a reason they think your boss, or whoever, is listening in on them.

The point is, it sounds like there's bigger issues at your work than this particular sensor.

Rather than agonize about who insulted whom, find another sensor with the original packaging, and show those other employees what the thing really is. It'll have a brand name, a model number, and perhaps even a picture on the package and in the installation instructions.

I think they're believing what they want b/c, as the person above me said, there's other stuff going on. They might just be blowing it off that it is actually a sensor to get what they want.

think my question is why are you taking this so personally? if I were them, I would also be suspicious of a device that looks like a microphone in my work area. don't act as though employers don't do this. it happens all the time. so they have good reason to suspect this.

I think you are in the wrong to be so angry. I think you should be empathetic with them. Do you know what that is? Try it

It could be "mcq316 and his boss don't know what that thing really is, they've been lied to!

It's not that they think you are intentionally misleading them to believe other than the truth, it could be that they think that you and your boss don't really know what it is. Maybe you have been "lied to" by the Big Bosses, how do they know? You could sincerely believe that the thing is a temp sensor and just not really know the "truth". Some people are just paranoid, too.

The bottom line is that if these employees have a problem, they can go to HR and discuss it. If they still feel that the device is a microphone, they can resign. The device stays put, they have no control over it.

As for you, you need to emotionally detatch from the situation. It's work, these are co workers, not family members or personal friends. Just blow them off as idiots and laugh at them for their idiocy. Only people who are basically insecure and have low professional esteem can be deeply insulted or offended by a work issue.

well no - the guy who told you this perhaps BELIEVES what he said - so technically he's not a liar - but on the other hand you don't have to believe what he says either.