And this meaning is close to the Mu'tazila in their saying that knowledge is obtained from correct reasoning by way of generation based on intellectual necessity, contrary to the Ash'aris who say it is obtained by way of habit. This is a testament to Ibn Tumart's rational inclination.

3. Homogeneity between the Root and the Branch: And its meaning is that the root, which is the command, and the branch, which is the ruling, are not in any way contradictory or conflicting, as if the root is an order to do something and the branch is a ruling permitting it or forbidding its action. Rather, they are always homogeneous and compatible. The command leads to the action, and the prohibition leads to abstention. If we find contradiction and conflict, it is evidence of an error in establishing the ruling as a result of attributing it to something other than its correct root. This error leading to contradiction arises from two things: the first is the establishment of a single branch from two contradictory roots. The second is the establishment of two contradictory branches from a single root. To prove the homogeneity of the root and the branch and their lack of conflict, it must be demonstrated that these two things are impossible.

A. The impossibility of a single branch being established from two contradictory roots: A single ruling, such as the prohibition of alcohol, cannot be based on two contradictory roots, such as one being a command for prohibition and the second being a command for permissibility. Al-Mahdi based this impossibility on four principles: The first is the impossibility of a branch being established without a root, because assuming two contradictory roots leads to the absence of the root, as the branch's connection to one is no more valid than its connection to the other. The second is the impossibility of the conjunction of opposites, because assuming two contradictory roots involves the conjunction of opposites in the root, which is impossible, and what it leads to is impossible. The third is the impossibility of the multiplicity of the identical, because assuming the attribution of a single branch to two roots necessitates its multiplicity due to the multiplicity of its source, which contradicts the assumption that it is a single branch. The fourth is the impossibility of the inversion of realities, because if the preceding realities are established in the mind and it is believed that the branch originates from the opposite of its root, then truth becomes falsehood and falsehood becomes truth.