The concept of truth may be problematic to philosophers, but I don't think it's that complicated for most scientists. In my experience, which is admittedly limited, scientists believe that there is an objective reality and that we are able to understand it. The scientists that I have spoken to about this also have a very nuanced view of how they are able to understand reality, and they fully realize that a model, whether mathematical or descriptive, doesn't fully capture reality, is prone to error, and must be continuously revised. For this to happen, scientists use evidence, and only evidence. Basically most scientists seem to have a common sense belief that we can develop models that roughly correspond to reality, and that we judge these models using evidence.
This fundamental belief about truth and evidence guides scientific dialogue, both in peer reviewed articles but also within the community at large. Whether at scientific conferences, gathered in small journal clubs, or over beers at the local pub, the conversations that scientists engage in are focused on how a belief corresponds with reality and what evidence would justify it. Scientists are just humans, so there's certainly a fair share of ridiculous opinions, poorly informed platitudes, and blind hero worship that crops up in any social gathering, but these don't gain much purchase before they get cross-examined for evidence. It is not only socially acceptable, it is a social imperative in the scientific community, that all beliefs be questioned and justified based on evidence, rather than expert opinion, general consensus, or emotional weight. This shifts even personal dialogue away from opinion and into a discussion based on truth, something badly needed in other social arenas, particularly politics.
Political issues are currently awash in opinion without reference to either truth or evidence. Discussion center on what each person believes, or their ideals, or their emotions, but by their nature participants in these discussions have little chance of finding common ground. There is no common ground if the issue is what I believe versus what you believe. Common ground comes from a hard discussion of our models of reality, usually called opinions, and how they are supported with evidence. This type of dialogue forces participants to cede ground when their opinion lacks evidence, and it removes many of the negative emotions associated with being wrong. Being wrong isn't stigmatized in the scientific community. In fact, it's almost celebrated. Scientists change their opinions a lot because they're not attached to being right; they're attached to understanding the truth about reality. This type of focus in the political arena would be a breathe of fresh air.
There a couple of limitations that I see to this sort of conversation taking root in the political arena. First, it would require people to be ok with being wrong and willing to change their opinion when they see evidence to the contrary. A lot of people hate this idea. Second, these types of discussions would require that participants actually pay attention to the facts. This means asking hard questions about funding limitations, embedded social structures, trade-offs, and risk evaluation. It means being honest about subjective priorities and values and their place within an evidence based discussion. Third, and perhaps the most difficult, it would require that citizens understand what constitutes evidence. This means that the anecdote and the feeling would have to be recognized as an important determiner of values, but not as a justification for a belief about reality. Rather than focusing on how people feel about issues like gun control or education, discussions would focus on real goals, limitations, and embedded trade-offs. This does not mean, of course, that feelings are unimportant. They are arguably one of the most important aspects of a political or social decision. This does not mean they are evidence.
How can society move towards truth and evidence based discussions, without everyone returning to school for a PhD in an already glutted field? Actually, I don't think it's that daunting, if we begin to utilize this type of conversation in our daily lives. What if it becomes socially acceptable in America to question a person's social or political belief, not maliciously, but in terms of evidence. More importantly, we should begin to question our own belief systems. Are we using anecdotes to justify broad generalizations, or feelings to justify a social policy? Without this type of daily practice, and without the social acceptance for this type of questioning, how can we question our politicians?
If you believe that there is no reality beyond a subjective social opinion, then the future is simply a bleak replacement of one social paradigm followed by another, with the face of power being the only thing that changes. But if there is an objective reality, as all but the most extreme Foucauldians believe, then our decisions regarding issues such as war, education funding, gun law, lgbtq rights, and a myriad of others, have real consequences for every member of society, giving each person a responsibility not just to themselves but to all. If reality isn't informing these decisions, if we reject evidence, then we are rushing blindly through the world, mistaking the volume of our voice for the light of truth.