"Let's try anger," I said.
"Anger?" Data looked at me quizzically.
Clearly, Data was not ready for my training session on "emotions". I knew he had an emotion program installed, but he had re-programmed it to be overrided by other programs where possible.
"Sure, anger can be useful sometimes," I said. "As long as you keep it under control. People like Captain Picard only use anger to express a sense of injustice or to show we mean business when we're backed into a corner."
"That appears to be a contradiction, commander," Data mused. "In all my understandings of anger, control is never exercised."
"I believe you are intelligent enough to exercise the necessary control, Data," I told him. "You are an android, after all."
"Quite right, commander. What shall I angry about?"
I thought for a minute.
"Let's say Captain Picard did not allow you shore leave on our last trip to Aldea. You were to stay on the bridge, even though you could have used a much-deserved break. How would you react?"
"But I don't require shore lea-"
"It's just an example, Data," I soothed him. "This is important. You need to be able to sympathize with your fellow officers who are put in the same situation."
"Very well."
Data scrunched up his pale face and narrowed his eyes, slumping in his chair and crossing his arms as he did so.
"Can you believe it?" he snapped. "Captain Picard assigned me bridge duty while the rest of the ship gets shore leave. As if an android does not need his circuits re-wired once in a while! What a two-timing fossil!"
My jaw dropped. Data relaxed his face and sat up smiling.
"Was that adequate?"
"I would go easy on the insults about the Captain, Data," I said. "Wouldn't want that sort of thing to get back to the Captain's ears."
A confused glance.
"But I thought you wanted me to relate to my fellow officers," Data said. "And I've heard a great deal of worse comments..."
"Okay, fine," I said, cutting him off. "That demonstration was good for our purposes. Now give me a moment to think of another emotion I can teach you."
"May I suggest one?"
"Be my guest."
"What about love?"
I looked at him in surprise. He didn't flinch, just looked at me with those grey eyes burning with curiosity.
"Oh Data, I don't know," I said uncertainly. "That's a pretty complicated one."
"It is an essential one to humanity," pressed Data. "All humans are born with an understanding of it. I understand parental love because my father wove that notion subconsciously into my programming. I understand physical love because my father installed a sexual drive. But love itself - the kind described in old Earth texts and the emotion which other cultures have attributed a multitude of words to describe its various forms - this I do not understand."
At this, Data's face became lost in thought and confusion as he pondered his lack of understanding. I instinctively moved closer to him.
"There's no one way to understand love," I began slowly. "For some humans, it takes a lifetime to understand it and some humans never understand it at all. So you're not alone in thinking you don't understand the concept."
"It is strange, that is all," mused Data, staring intently at the floor. "I understand the abstract concepts of space and time, of mathematics and computation. But love eludes me."
"Well, I'll try my best to explain," I conceded.
He looked up at me expectantly. I avoided his gaze, but I rested my hand lightly on his.
"I think love is when two people care about each other deeply," I explained carefully. "It's a very intimate, tender and warm feeling of affection that goes beyond everyday loyalties and friendships. Love, that is the best kind of love, is developed over time, as you get to know the person better, and then suddenly you discover you can't imagine your life without that person. They suddenly become the most important thing in your life."
I paused, trying to see if I had missed anything.
"Does that make sense?" I asked at last, looking up at Data.
*Commander Freya, report to the bridge for duty* blared the intercom.
"For now, commander," came the reply.