The principle on which they based this is exceedingly weak, although it has caused confusion among many later scholars.

By saying, “The Necessary Existent can only be one,” they intended to deny that He has knowledge, power, life, speech, or any other attributes subsisting in Him. For, they argued, if He did, there would be more than one necessary existent. Similarly, the Muʿtazilah say that He has no eternal attributes subsisting in His essence, because otherwise there would be more than one eternal existent.

The terms “necessary” and “eternal” may refer to God, the Creator—glorified is He—who necessarily exists and is eternal. In this sense, there is only one. They may also refer to His beginningless attributes, which are eternal and necessary by virtue of the pre-existence and necessary existence of the One they qualify. This does not entail that they must be like Him, nor does it make them deities, just as a prophet’s attribute is not itself a prophet, and an attribute of a human or an animal is neither a human nor an animal. Likewise, if an attribute of something that came into being also came into being, their both having come into being does not imply that they are alike. The argument they have offered for their claim is weak.

Thus, if they say:

“If He had knowledge that was necessary by virtue of the necessary existence of the Knower, there would be more than one necessary existent,”

they may be answered:

“Why do you say that there cannot be more than one necessary existent, when the necessarily existent essence is one God endowed with the attributes of perfection?”