Clearly I am heavily biased. But I think it's most appropriate for people dominant in a function to discuss the effects of not having a certain function exist. Clearly though, as i've said earlier, it's a little inappropriate to isolate individual functions.
For this reason;
I actually like the rudder metaphor.
I think Fi is the rudder, at least for an Fi-user.
But for an Fe-user, Fe-is the rudder...
Now for
humanity, hmmmm...
I would say for humanity, there is no single rudder.
There are thousands of rutters constantly trying to push the world in their own direction.
Brilliant!!!
Ever heard of the stanford prison experiments? (where all of the subjects were separated into 'guards' and 'prisoners' and the guards started literally becoming abusive, disrespectful intimidatory within a very short space of time).
Or the Milgram experiments where subjects were tested on their personal conscience, under the authority of psychologists who pretended to be "scientists" where given instructions to 'electrocute' other subjects? (where most people did exactly what the 'scientists' told them, even though some were 'screaming' - although it was fake, in 'pain'?).
What some social psychologists deduced from these experiments, was that people were capable of doing
anything, regardless of the consequences, given the circumstance (especially given permission by authority).
I dare say, Fi might allow someone to move through these morality tests. When I grew up I never needed to be told how to behave; I was aware of all the consequences of my actions, even as a young child. As a very small child, I knew what hurt other people psychologically, emotionally, physically etc, and I decided the negative consequences that come from moving against people, outweigh the positives in most situations. It's like the opposite of game theory. It's able to see the holes in
game theory instantly, that John Nash is only seeing/admitting now.
I think all functions operate on a brilliant balance continuum. I think Fi brings something important to an arguably Te oriented world. But that said, I can see how many people see it as irrelevant or a bother. It sometimes deals with things that most people don't deal with. But without Fi, the world would probably lose a lot of psychologists and counselors. It may lose the people in science who communicate well to the mass public. It may lose a lot of activists, campaigners, lawyers. A lot of people who others would term, 'unsuccessful' and 'bums'; but they probably don't care because they define 'success' in different terms. They define success as 'integrity' to their own self. It balances out Te, and i've seen a few Fi-dom teachers, show Te-dom students a way of life that gives them a sense of liberation.
A lot of people say Fi just leads to misery, hopelessness etc. No, that comes from how a person thinks. Fi as a pure cognitive function, gives worth, meaning, depth of subjective knowledge, values things in subjective terms. The world could do without it sure, but it would take away the colour and depth of experience for many people. What are we all alive for? just to procreate and make money? what is living really about? what society tells you is being a successful human? (remember, how the world is, doesn't make it 'good').