''Yes, Scientists believe in God''.

[Edwardo Piet]

Yes. Very important point here. Utility doesn't make something true.
Evf

Then what does make things true?

Scientific evidence can make something to be as accepted as the best possible scientific explanation. About as close to 'truth' as you can get really I think. Not absolute truth...but then if truth only=absolute truth then when do you use the word truth?
The best scientific explanation is closer to the truth than just thinking something is true because its useful! If something consoles you or helps you in some way. That doesn't mean that it exists!
The more evidence of it and/or its truth the more likely it does exist and/or its true. I don't see how utility makes it, or would make it true. I don't really believe in known absolutes, or even absolutes. I dunno.
Evf