Is Self Impostor Syndrome (SIS), a trait you obtain in your search in Life?

I'll try to explain it better and quick.

In the endless and obscure path we all walk on our own River that is our Time and Life, we all obtain experiences that shape us throughout the years.

If we will but observe these situations that come to our life's and learn the "lessons" we are to learn, you will obtain a deeper understanding upon certain subjects that I can only put them under the term of "Life".

But as Socrates had said "I know that I know nothing" , this whole subreddit it's about the effects of that knowledge. If you become very good at whatever area you are training or working on, you will know that, yes you might know a X amount of stuff but oh God there are so much more. In life's lessons tho, this pattern have personally filled me more with a self impostor syndrome some times than a strong feeling of knowing what is right.

There are some fundamental things that most of humanity can agree upon yes, but i just can't figure out where this SIS Is coming from. Is it a stage you achieve before becoming more confident in your knowledge or is it a byproduct of the knowledge you obtain itself? Thoughts?