Took a few minutes, but I found it:

“But another question arises: Man’s condition is one of utter helplessness and absolute poverty. All might and power belong to God alone, and man’s exaltation and abasement depend on the will and purpose of the Most High. Thus it is said in the Gospel that God is like a potter who makes ‘one vessel unto honour, and another unto dishonour’. Now, the dishonoured vessel has no right to reproach the potter, saying, ‘Why did you not make me a precious cup that would be passed from hand to hand?’ The meaning of these words is that souls occupy different stations. That which occupies the lowest station of existence, like the mineral, has no right to object, saying, ‘O God, why have you denied me the perfections of the plant?’ Likewise, the plant has no right to protest that it has been deprived of the perfections of the animal realm. And, similarly, it is not befitting for the animal to complain of the want of human perfections. No, all these things are perfect in their own degree and must pursue the perfections of that degree. As we have said previously, that which is inferior in rank has no right or qualification to aspire to the station and perfections of that which is superior, but must progress within its own degree.” (‘Abdu’l-Bahá, “Some Answered Questions,” p288, para. 70.5)