No no. In the dark days people believed various things were true because authorities said so - authorities such as the Church, Plato, Aristotle, whoever. People

No no. In the dark days people believed various things were true because authorities said so - authorities such as the Church, Plato, Aristotle, whoever. People confused truth with source and also believed that some ideas were certain or self-evident. The Englightenment was a rebellion against these attitudes. In reality we are fallible and we now expect that some of what seem to be our best ideas are in fact wrong, including our current values. If this weren't the case, progress would not be possible, as I think you rightly acknowledge.