Sahar in Arabic means to prove wrong as Right , this is how logic does which offers such amazing & Batil reasons/logic that every wrong myth proves to be a reality. This is that branch of knowledge which proves every falsehood with amazing & mind boggling reasons.This is actually Sahr. Those wise intellectual when opposed this logic they embraced sufism .
Whatsoever is proved by rationalists through logic ; the same is proved by sufism through wonderful examples & parables .
Ghazali spent half of his life as rationalist who proved wrong as right through these rational logic while the rest of his life passed in proving his own myths as falsehood. ie He started to worship bigger gods in place of smaller .This is why the wisdom/intellect should always be subjected to the telescpoe of the supreme wisdom which provides the concrete & positive reasons to quench the thirsty & self-centered wisdom.