One assumes, a priori, that a parent would be better at dealing with problems.

人们通常推论，父母更善于处理问题。

So a priori, this was not necessarily true.

所以先验的并不一定是正确的。

At any rate that certainly is not knowable a priori.

不管怎样，那肯定不是一个可知的先验。

But we have no way of knowing a priori that they are true of the world.

但是我们无法知道先验是否真实存在。

In other words, the frequencies of those waves should be constant in time and space a priori.

换句话说，那些波的频率根据推断在时空上是常定的。