in the strictest sense:
that which enables technology.
Science is in its criteria purely empirical.
Analytics allow us to repeat processes, that is all.
2
further question:
What is technology?
Heidegger, the 20th century embody this question.
The answer is: that which connects man to shared powers which are greater than his individual ones.
A concept is a power. A stick is a concept.
3
Truth
Science reveals, layer by layer, the nature of power.
Or: it teaches us truths.
"Thus it must be rooted in truthfulness."
That is not a foregone conclusion - it can just as well be the erring that teaches the value of truth, which in turn allows (some) discernment of it.