Sorry but scientific method has been the default for "Truth" for many academic subjects. It is reliable and idempotent. If all of the human information and most of the knowledge workers are removed from the Earth tomorrow, many will arrive in the same conclusion in most of the natural sciences and maths. The language and representation will be different but prime numbers will still be prime numbers and the matter will still be made of one neutral and two "interactive" elements.
Social sciences like politics, history and economy are harder to replicate with the scientific method, however repeated observations, statiscial information as well as qualitative analysis with evidence-based research can still provide replicable analysis.
> If anyone has a better idea how to determine what is true and what isn't - i'd certainly be very interested
This kind of excuse is often cited to shut down any discussion, especially in history, politics and economics. I find it deeply anti-intellectual and dogmatic. As long as evidence and counter-evidence is followed, it should be possible to discuss alternative interpretations and solutions.