Building bridges and bursting bubbles.

Anytime we address new interlocutors, we engage in a constant recalibration of our common assumptions. And, why deny it: preaching to the choir feels better than talking to a wall. Yet, we don't want to be preachy, at least not admittedly. 
This takes me back to @blake's humility and pride dialectic... My question is:

I'm all in for building bridges and bursting bubbles, and I it's almost a mantra for a lifetime project of mine. But I have to constantly remind myself: who's 'in charge' of designing the bridges? What's the most gentle way to burst someone else's bubble, if we deem it necessary?

An example: this very morning I brought up Gandhi to my 17-18 year old highschool students. No one knew who he was. For a moment I had the urge to find a scream booth somewhere near, but after discarding the possibility, I proceeded to introduce the guy and his works to a new audience.

By now you can see I am assuming you know who Gandhi was, but how can I possibly tell, this is a new audience to all of us! What common grounds are we relying on? Are we aware of them? For instance, most of you are English native speakers, while I'm not, so now I'm sort of bracketing other idiosyncratic and linguistic stuff I carry around, in my attempt to (co)build a bridge with you... Or burst a bubble in an almost gentle way...

I sincerely hope you are looking up and/or not looking up Gandhi on Wikipedia right now (yes, both at the same time, mixed feeling or what have you...) Let me know what you think and feel (which can't be separated) about this...#DeepTakes