Critics say the words 'in the truth' turn minds on. Jehovah's Witnesses are programmed to trust and consider the viewpoints of people who are 'in the truth' just like them. There is a feeling of superiority and being better than people who belong to 'false religions'.
Critics say the words 'out of the truth' turns the minds of Jehovah's Witnesses off. Why? Because what's the point of seriously considering the facts or opinions expressed by someone who doesn't have truthful information? Jehovah's Witnesses have no reason to spend much time listening to people who are outside their religion.
No matter how convincing the evidence, Jehovah's Witnesses know it would be foolish to change their beliefs. Why? Because they believe they are 'in the truth'. 'New truths' always come from the latest Watchtower and it is the only source they trust of truthful information. All other sources can't be trusted because the information is presented by people outside their organization who are 'out of the truth'.
To understand the power behind these innocent looking words 'in the truth' and 'out of the truth', check out these articles: