We all supposed that those information we have received is knowledge. However, in terms of philosophy, especially in Socratic wisdom, knowledge is part of the truth. All information in the lower world is only opinions. No matter those opinions is truth or not, they are illusions compare to the truth. Therefore, all information we have grasped, maybe useful for life, academic or science, does not represent the truth.
See Plato's "Meno", "Theaetetus"