This Natural Science book talks at the beginning of the chapter about the Muslim caliphs ordering the burning of the library of Alexandria in the 600s or 700s, implying how awful it was that Muslims destroyed so much learning. To quote,
"With the fall of Rome, Greek science was almost completely lost. The Greek world soon fell to Islam. The Arabian conquests began after the death of Mohammed the Prophet in 622 and lasted for about 100 years. The Arabian empire was an absolute monarchy, ruled by a caliph who was believed to be a successor of the Prophet. When the conquerors came to Alexandria, the caliph was asked what to do with the books. He replied, "If they agree with the Koran, they are superfluous. If they disagree, they are pernicious. In either case, burn them." But not all the works were destroyed. Some of the information was preserved by Arabic, Syriac, and Hebrew scholars, translators, and philosophers who lived in the Arabian empire of Islam."
Boo! Hiss! Those intolerant and ignorant fanatics destroyed the Library because it disagreed with their theology! But then later it talks about how it was burned by the Roman-Christians in 389 because the books therein disagreed with *Christian* theology. To quote,
"In about 295, the Roman emperor Diocletian issued an order to burn all alchemical writings in an attempt to halt the counterfeiting. The library at Alexandria was burned in 389 to eliminate alchemy as a competitor with theology. The alchemists modified their approach to give the appearance that alchemy was compatible with Christian theology."
For one thing, the caliphate was not the first party to burn down the library of Alexandria. For another, there wasn't much left for the caliphate to burn by the 7th century. Heck, there wasn't even much left to be burned by Diocletian, much of the library was destroyed or lost when Emperor Aurelian took the city in 274 CE. And that was just what survived from when Caesar *accidentally* burned down the main library during the siege of Alexandria in 47 BCE!
Instead of making a (thoroughly valid) point about the destructive nature of religious fanaticism, they should have instead touched upon the dangers of storing your civilization's knowledge in easily burnable forms. Clearly, the Sumerians had the right idea.