If you want to begin to develop your critical thinking skills and your intellectual discipline, read the Surat-al-Kahf.
In the very first story you will learn something about the importance of keeping focused and avoiding conjecture and irrelevant tangents. How many youths were they? How long did they stay? What about the dog? Allah tells you, basically, how foolish these types of questions are, how pointless, how immaterial. Focus on what matters in the story.
And in the story of Nabi Musa and Khidr, similarly, we see the importance of focus and intellectual discipline, as well as the importance of knowing how to behave towards those with more knowledge than we have; and this principle extends to how we should deal with authentic and reliable sources of information, versus our own opinions, emotions, and perspectives. We learn the error of forming opinions without adequate information.
Nabi Musa knew from Allah that Al-Khidr had more knowledge than him, yet he repeatedly pestered him with questions that called Khidr’s actions into doubt. Musa could not be patient, just as Khidr had known he would not. Nabi Musa could not help but jump to conclusions based on the partial information he had, rather than waiting, reserving judgment until all the facts were explained to him.
SubhanAllah, although Allah told us to ignore irrelevant matters, we still find today those searching to discover what was the location where the two seas met, who exactly was Dhul-Qarnayn in history, where was this place or that place mentioned in the Surah…let us not miss some of the most valuable intellectual lessons Allah gave us in Surat-al-Kahf; for we can find in this Surah the basis for liberating our minds from many mistakes that have become common in our thought processes.