Meaning of "then" in the context?

Question

"...whatever philosophers say about themselves, there is no philosophy which does not embody a class outlook, or which is impartial, as opposed to partisan, in relation to class struggles. Search as we may, we shall not find any impartial, non-partisan, non-class philo­sophy.

Bearing this in mind, then, we shall find that the philo­sophies of the past have all, in one way or another, expressed the outlook of the so-called "educated" classes, that is to say, of the exploiting classes.

...

We can only conclude from this that the working class, if today it intends to take over leadership of society, needs to express its own class outlook in philosophical form, and to oppose this philosophy to the philosophies which express the outlook and defend the interests of the exploiters."

Maurice Cornforth, Materialism and Dialectical method

I have two questions to ask

1. The word "then" has some meanings but what does it mean in the context?
2. I don't know the use of "to oppose something to something else". Could you explain it to me?

Many thanks!

Answer 1

"then" seems to mean "consequently" or "it follows that"

as in a logic or math course, where they say: "if P 'then' Q,"

given one proposition as true, "then" the next proposition is true.

"to oppose" seems to mean to set up an opposing philosophy for public competition to convince others of the working class point of view and interests