Assuring certainty is a huge way of persuading people and make people follow you. People are take note and become attentive when you prove that you are certain about something. It could be positive or negative, but if you are confident about it and show them certain solution, they jump with you. Our brains are a slave to familiarity and certainty. The more familiar they find something and the more certain they feel about something the safer they feel with less inhibitions. So make people feel comfortable, certain and familier and you have their support.
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