As I said, it depends on how you define truth. If it’s enough that people agree with you, your distance from the generally accepted truth can vary widely, depending on the donor of people you base it on. The fact that people agree with you doesn’t make something true on its own.
Effectively the question is: How reproducible do you want your truth to be?
If you only need your buddy to come to a similar truth you may not need to argue that much. But to convince a perfect stranger you will probably have to make your case properly. How did you arrive at your truth? Which conformable facts do you base it on? Which predictions does your claimed truth make, that might validate it?