The prototype disbeliever who is challenged by the number 19 is described as the one who makes erroneous inferences (74:18-20). The repetitious reference to his fallacious logic emphasizes the importance of thinking and inferring properly.

God has embedded in our hardware and system software the rules of logical thinking (rooh and aql), which amazingly work perfectly in harmony with the rules of external or natural world. If we employ these rules they will help us to understand God’s law in the nature and the scripture. Our ego, our weakness to follow the crowd, our short term petty interests and similar interference can prevent us from employing those rules correctly or efficiently.