The generality of the Ash'aris hold that it is an obligation for each person to know the proofs for the existence of his Lord, through rational and observational proofs and some of them (such as al-Baqillani) go to extremes in claiming that each and every person must learn the preliminary philosophical precepts that underlie the demonstration of Allaah's existence through al-jawhar wal-'arad (substance and accident), and some of them go to even more extremes and make takfeer of the one who died without making this inspection and inference (an-nadhar wal-istidlaal) in order to prove the existence of a creator rationally, whilst he had the ability to do so!

And this foundation (asl) is a foundation that belongs to the Mu'tazilah and the Ash'aris (once again) simply borrowed it (thanks Mu'tazilah!).

Al-Qadi Abdul-Jabbar al-Mu'tazili on The First Obligation

Al-Qadi Abdul-Jabbar (d. 415H) says in his "Sharh Usool il-Khamsah", at the very opening of the book:

... So he (al-Qadi Abdul-Jabbar) said: If a questioner asks: "What is the first (thing) that Allaah has made obligatory upon you", then respond: An-nadhar (inspection, observation) that leads to knowledge of Allaah the Most High, because He, the Most High is not known by necessity and nor by direction seeing, thus it is obligatory that we know Him through reflection and observation.

And he also said (p. 70):

...When this is established then know that the intent by our saying that "an-nadhar (inspection, observation) is the first obligation in the way to knowing Allaah", is that it is from those obligations that the mukallaf (the person bound by the Sharee'ah rulings) can never be separate himself from any angle whatsoever...

The Extreme Views Held by Some of the Ash'arite Theologians

First lets see what Imaam al-Juwaynee says in "ash-Shaamil Fee Usool id-Deen" (p. 115):

Observation (an-nadhar) and inference (al-istidlaal) that lead to acquaintance of Allaah, the Sublime, are two obligations...

And further on (p. 122):

... And if time passed by - from the time that religious obligations applied to him - in which he had the capacity for an-nadhar (observation and deduction of proof, rationally) leading to knowledge, and he did not inspect, despite there being no preventive barriers and he passed away after the time in which this was possible for him - then he is put alongside the disbelievers...

Al-Juwaynee here says regarding the one who did not make observation and inference, despite having the capacity to do so before he died, is considered a disbeliever. And this is one of the more extreme views amongst them, whereas the others simply emphasize that knowledge can only be perfected through an-nadhar and al-istidlaal and that the first obligation is to observe, or have the intent to observe (in order infer from it the fundamentals of faith, such as a Creator and so on) and they differ regarding the one who abandons it, with al-Juwaynee's view being the most extreme of the views.

Ibn Hajr Refuting This Mu'tazili Foundation That Remained With the Ash'aris

Ibn Hajr first makes mention of the positions of Ibn Fawrak and his followers, and also that of Abu Bakr al-Baqillani and Abu Ishaq al-Isfaraa'eenee (all Ash'aris - being students of Abul-Hasan al-Bahili, the student of Abu Hasan al-Ash'ari) on this subject.

So in the course of discussing this issue, Ibn Hajr rebuts this position of the Ash'aris saying:

And I have mentioned in "Kitaab ul-Eemaan" the one who turned away from all of this [i.e. what al-Baqillani, Ibn Fawrak, and al-Isfaraa'eenee are upon] from its very foundation and who held on to His, the Most High's saying "So set your Face towards the upright religion, Allaah's fitrah (meaning Tawheed) to which He has made mankind to be inclined..." (ar-Rum 30:30) and the hadeeth, "Each child is born upon the fitrah (i.e. inclination to Allah's recognition and Tawheed)..." For indeed the apparent meaning of the verse and the hadeeth is that knowledge (al-ma'rifah) is already acquired on the basis of the fitrah, and that (a person's) departure from that is through what (subsequently) happens to a person, due to his (alayhis salaatu wassalaam), saying "...then his parents make him a Jew or a Christian..."

And Abu Ja'far as-Samnaanee - and he is one of the heads of the Ashaa'irah - has agreed with this, and he said: "Indeed this one of the issues of the Mu'tazilah that remained in the saying of al-Ash'ari and branching off from it is (the saying) that the obligation upon every person is to have knowledge of Allaah through the evidences that point to Him, and that taqleed is not sufficient in this regard."

So here:

• Ibn Hajr rebuts this position (of the main early Ash'ari scholars) very clearly and unequivocally, as he has also done previously in Kitaab ul-Imaan (see part 1 of this series) - with just one verse and one hadeeth.

• Ibn Hajr makes mention of as-Samnaanee who agreed with what was correct and had to admit that this issue was one that remained with al-Ash'ari from his Mu'tazili past.

Imaam an-Nawawee's Refutation of the Asha'rite Theologians on This Issue

Commenting on the hadeeth, "I have been ordered to fight the people until they testify that there is none worthy of worship except Allaah (alone) and until they believe in me and what I have brought..." (Saheeh Muslim), an-Nawawee says in his Sharh of Saheeh Muslim (1/210-211):

In (the hadeeth) is a clear evidence for the madhhab of the muhaqqiqeen (those verifying what is correct) and the majority amongst the Salaf and the Khalaf that when a person believes in the religion of Islaam with a firm and resolute belief devoid of any doubt, that this is sufficient for him, and he is a believer amongst the Muhawahhideen. [And that] it is not obligatory upon him to learn the evidences of the Theologians and knowing Allaah, the Exalted, through them. [This being] in opposition to the one who made it obligatory and made it a condition of a person being from the the people of the qiblah [and who] claimed that he does not have the ruling [applicable to] the Muslims except through this. And this madhhab is the saying of many of the Mu'tazilah and some of our associates, the Theologians (Mutakallimoon), and it is a manifest error...

Summary

The Ash'aris are in agreement with the Mu'tazilah on the issue of an-nadhar wal-istidlaal - and their foundation (asl) in this regard is the one and the same, and some of them have extreme views in this regard.

And the reason for this is that the Jahmiyyah and Mu'tazilah were the pioneers of the proof called "hudooth ul-ajsaam", a corrupt, false proof for demonstrating the universe is created, and as a result of it they were forced to reject what Allaah affirmed for Himself of Names and Attributes - in order not to falsify this proof, and in order to avoid the Philosophers ending up on the floor laughing at them for trying to prove the existence of a Creator with a proof that actually disproves His existence. So the Mutakallimoon (the Jahmiyyah, the Mu'tazilah, the Kullaabiyyah, the Ash'ariyyah, the Maturidiyyah) were force to play around with the revealed texts through ta'weel, tahreef, tafweed and pure ta'teel in order to avoid falsifying this intellectual proof.

And as such, many of their usool (foundations) and positions are exactly the same in reality even if they make a pretence of differing from the Mu'tazilah and the Jahmiyyah.