I can't even begin to count the number of times that Brent Spiner's brilliantly portrayed character has reminded us all of our own humanity. What it is to be human. Reminding us of our morals and of how at times we as humans are capable of behaving in a rather bizarre manner. Especially when emotions get in the way and gum up the gears.
For me, I believe Data is the entire reason I watch Star Trek: The Next Generation. It would still be a good show without him. Possibly. We'll luckily never know. And I say luckily because really I don't even want to try to imagine what that would be like. Data brings a childish light to the show and like a child he asks questions. Questions of what he observes of humans: Why do people choose to trust and risk being hurt in the process? Why is it more painful when someone we are close to dies? Shouldn't we show the same compassion for all humans? If someone is comfortable as they are and their behavior is not self destructive, then who are we in our infinite arrogance to tell them they have to behave differently?
Somehow he has a way of taking all these serious human issues, raising them and displaying them for how simply they truly are. Although this happens within Star Trek as a whole I believe the Universe is the limit when it comes to the things Data makes us contemplate about ourselves.
Most inspiring of all I believe is that despite the knowledge that he can never be human he still tries his best to emulate one. To become more than just the sum of his parts. Despite his faults he tries his damnedest to become more then just circuits, metal and bioplast sheeting. He endeavors to be acknowledged as a living sentient being and to be treated as such. I believe all of us in our own ways feel similar to this in our own ways. Aren't we all trying to be more than just a yapping bag of mostly water? Organs, bone, and muscle. Who doesn't want to be seen as more than that? Aren't we all trying to grow as in our work places, grow in our relationships-- grow as people? I'll let you go now. This is becoming a speech.
"I chose to believe that I was a person, that I had the potential to become more than a collection of circuits and processors. I took a leap of faith." -Lt. Cmdr. Data (ST:TNG "The Rightful Heir")