There are 3 stages of pramAna (evidences) primarily. anumAna (inferences or derivations of new knowledge from other proven truths), pratyaksa (verified explicit current studies), sabda (peer reviewed, proven knowledge accepted by all and transmitted). Anumana should lead to pratyaksa which should then lead to sabda. That's how knowledge evolution should work.
If anumAna does not become pratyakSa then it's just our imagination. If pratyakSa does not become sabda or widespread accepted knowledge, then it's lost knowledge or still unproven knowledge. So unless claims go through all 3 pramAnas, they don't become veda or knowledge. Unfortunately people mistake anumAna itself as knowledge. When they turn it into successful business, it becomes psuedo-science.
Mostly people consider these pramAnas as 3 types of pramAnas, which are independent. I differ. While it's true they are 3 types of pramAnas, I also see them as 3 stages. The success of modern science is that it sees these pramAnas as three stages and ensures claims are taken from anumAna to pratyakSa to Sabda.