Francis Schaeffer was a devoted and orthodox Christian, and great thinker of his time.
He was a genuinely good man, and genuinely worthy of our respect.
But he was writing in a time when there weren't really many Christians working in philosophy.
He did something new in his time; he took a broad assessment of the Christian "world view" by drawing from many different fields to synthesize these insights into a broader philosophical paradigm. He had a lot to say about history, culture, art, politics, and apologetics... but although he did a fine job thinking through "big picture" issues which orthodox ministers had neglected for a long time, I don't think his works should be considered the pinnacles of Christian thinking on these topics. I would consider him (looking backward from our current place in history) as a good starting point to begin thinking about Christian philosophy and those "big picture" views we now call a "meta narrative."
We've had a resurgence in Christian Philosophy since Schaeffer first began his assault against the Christian liberalism that was destroying the church, and destroying Christian academia in his time.
We now have lot of great minds devoted specifically to Christian Philosophy and Christian Apologetics.
I would suggest starting with Schaeffer, but them moving on to other orthodox Christian theologians and philosophers.
There is still a real fight against liberalism, and all it's endemic philosophies which are poisoning the church, but we have a lot of great thinkers now devoted to that fight.
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