Atheists have self-conceit and pride.

God - be glorified - said in the Quran 67: 20
{إِنِ الْكَافِرُونَ إِلَّا فِي غُرُورٍ}

The explanation:
(The unbelievers are only in self-deception [with their wealth, their sons and theirlarge number.])

Any qualified man has only limited knowledge: he studied some books and made some researches: and whatever knowledge man acquires , this knowledge is only very little.

Whatever knowledge man may have, it is only relatively very little in comparison to the marvels and secrets embedded in the entire universe.

As God said in the Quran 17: 85
{وَمَا أُوتِيتُم مِّن الْعِلْمِ إِلاَّ قَلِيلاً}

The explanation:
(And you [people] are given only a little knowledge.)

Examples:
Some atheists claim that there are many mistakes of flaws in the creation, and they cite for us many examples like the recurrent laryngeal nerve, and say that it goes to the chest then returns back to the larynx; and in giraffe it extends downward for considerable distance because of the long neck of the giraffe.

I say: they have only little knowledge, and while they don't know the wisdom from creating the recurrent laryngeal nerve, then they come with their defective little knowledge and criticize something they don't know, and on this notion they base their doctrines and beliefs.

By the way, they worship something like the Totam, which is Nature.

But they are wrong now, as were they wrong in the past when they thought the appendix in the abdomen of man is only accessory and has no function.

While now they have become aware about the advantages of the appendix to man.