Intrapersonal

At first glance, being intrapersonally intelligent is stupid. It's generally the last in the list of intelligences. Probably because it's rare, perhaps more likely because it's the least useful. Honestly. It's easy to see how naturalistic intelligence can help with farming and food, logistic/mathematical intelligence with engineering and science, spacial intelligence with art and creation, linguistic intelligence with practically everything...

They are all so obviously useful and beneficial to others. Intrapersonal? Not so much. What is so good about being in-tune with and knowing your own self? How does that help anyone?

My conclusion (a half-baked one) is that we can be examples, at least, and very empathetic at best. Introspection is the star quality in intrapersonally intelligent people. It's second-nature to reflect and disect our feelings, thoughts, motivations, strengths, and weaknesses. Generally, this breeds ethical behavior and motivations along with self-regulation.

From Udemy blog's Jesamine's article on intrapersonal intelligence:

Introspection

Introspection is the deliberate act of looking inward in order to gain insight into the nature of one’s own thoughts or feelings. An introspective person wants to understand why he or she thinks, feel,s or acts in a certain way, not as a means of justification, but rather as a means to better understand what might be working “behind the scenes”. If he or she uncovers jealousy or envy, then that will further be explored. Where does the jealousy come from?  Why am I envious? If fear is discovered, then he or she will want to go to the roots of that fear in order to find out where it started.  A person who has explored his or her inner depths in such a way develops an entirely different level of ethical awareness, one that goes far beyond the simplicity of a conventional ethical system."

Reading this has helped me understand why I annoy my MIL so much when I ask why she does/has done certain things. From whay I've been reading, it's just not normal for people to analyze their actions so deeply. They don't sit there for hours thinking about the patterns and motivations behind them. It may also be why she thinks I'm selfish. Thinking about myself all the time certainly does seem selfish!

But it has it's place. Introspection and self-awareness are important. Most of all, I think it fosters empathy and exploration of the feelings of others. We're naturally equipped to ask the deeper questions, we just need to help others apply it to themselves. 

All said, it's still the most self-serving of all the intelligences, and I'm not proud it's the most prevalent in my persona, but it's there.