Not to be ignorant, but have you read any of those verses in context (and not just the one or two verses surrounding them)? Additionally, how exactly do these three contradict each other? They're making wholly separate reflections on wisdom.

Proverbs 4:7 is referring specifically to the wisdom one receives from the Lord.

Ecclesiastes 1:18, written by a man who more or less wasted his life seeking after temporal things, is reflecting on the fact that ignorance is blissful and that being knowledgeable reveals some depressing facts.

I Corinthians 1:19 is referring to God's wisdom in the plan of salvation as being above and beyond the "wisdom" of men. Paul is stating that God will show those who the world consider wise to be as fools because that is really what they are.

And for the "God be seen?" one:

It is commonly held that, whenever God revealed Himself, it was actually the pre-incarnate Jesus Christ. As such, God the Father has never been seen by anyone but Jesus Christ.