That sentence is definitely true. But I'm not trying to argue that there is no objective truth, my point is that real world issues, especially human and social realities are composed, and the result of, the interaction of many objective truths. It is very tempting to feel we have cracked a difficult problem just because we have uncovered incontrovertible evidence of something or other. Its the "one data point" fallacy dressed up in scientific clothing/

The truth sometimes lies in between, or is some combination of, two opposing sides of an issue: a midpoint on a spectrum. And sometimes it lies at right angles, and all the charts and footnotes are irrelevant because other factors are at work and dominate the issue. I.e., the spectrum is an artifact of our cognition, not a representation of the reality.

Again, I'm not advocating some indeterminate quantum social universe where anything goes and no opinion or principle can be justified. We have to make choices, and very often on the basis of insufficient data. What I'm saying is we can't always speak with certainty on any issue, there are always counter-examples, exceptions. Rather than commit ourselves to Truth, we should instead attempt to maximize our probability of success. The universe itself is not one of binary alternatives and infinite precision. But statistical mechanics does work; maybe we should try to maximize the odds instead.