"The hope that we might be able to base policy on definite knowledge of the causes of violence is receding."

They have no definite knowledge thereof but only follow a conjecture.

Indeed, the whispered laugh that sounded in the darkness was evidence of definite knowledge.

As yet, The Shadow had no definite knowledge of the final destination.

But there would still be too little to amount to definite knowledge.

In any case, in the absence of definite knowledge, we might as well look where it's easiest to see.

He appears to have a passion for definite and exact knowledge.

General Grant's early indulgence in liquors had long been a matter of wide, though not very definite, knowledge.

Unfortunately, any definite geographical knowledge that he included in his map is lost as well.

By this method, we have gained definite knowledge with reference to metaphysics.