In the early church holy spirit allegedly gave witness (god's spirit bears witness with our spirit) by means of special gifts.
Speaking in tongues (ecstatic gibberish labeled the language of angels), prophecy (lucky guesses - the more guesses
the lucker the prophet becomes), healing of people with psychosomatic illnesses.
For God's spirit to be a witness it has to give an external visible sign otherwise it's just a person bearing witness to themselves.
Basically, those who think they have been "chosen" because the words of a scripture had some kind of emotional
connection with them are really experiencing a sort of halucination. People who feel out of the norm and want to be special are always looking
for something that will confirm that feeling. Some think they were from another planet. Some think they were famous
people in a previous life. Some, like Oprah, think there is some special magnetic force that draws them toward
success.
In other words, The Watchtower is, at its foundation, led by some pretty crazy folks.