>it is close minded to say that substance like DMT or Ayahuasca induce no "changes" after the effect.

No one said that they induce no changes. Read the post. 

>It can "take" the conscientious part of the brain and let it see (introspect) the unconscious part. I've known someone who has had a powerful positive change induced by such things.

Here. Let me try to bullshit my way through as well : Through the drug, your inner introspective consciousness can reflect your subconscious physical reality.

^ See what I did there. I stringed together words that mean nothing and appeared to be a spiritual smart-ass

>We should not underestimate knowledge from ancient civilisation, I went to Columbia where indigenous live in the "jungle", they have developed a knowledge that had permit them to survive thousands of year in an environment where we would die in less than a week (seriously).

So what? this means nothing. There are still in the jungle right?

>Some of their knowledge practice and rituals are garbage, but we would certainly be surprised by how much knowledge we have skipped of forgotten due to our close minded approach.

Not really. most of the "inner" knowledge is just sitting around doing nothing, listening to the birds. in other words. The inner peace of chillax.