"Dissatisfaction is a good thing if it is for better advancement. That is wanted. Dissatisfaction. Just like the karmīs, they are also dissatisfied with 100,000 of dollars. That means they want to make one million thousands of dollars. So that kind of dissatisfaction for the karmī is good, because he can increase further assets. Similarly, if I am dissatisfied spiritually or I am not making advance, I am still on the material platform. That is good. That dissatisfaction is... Socrates also. Yes. And ass, cats, dogs, they are satisfied with a morsel of grass, that's all. You see? A little stool, what is the value of that satisfaction? What is the value of that? That is our philosophy. Just like Caitanya Mahāprabhu is dissatisfied. What is that? Kadā tava-nāma-grahaṇe bhaviṣyate.
śūnyāyitaṁ jagat sarvaṁ
Nayanaṁ galad-aśru-dhārayā, cakṣuṣā prāvṛṣāyitam. What is that verse? Nayanaṁ galad-aśru-dhārayā? Pulakair nicitaṁ vapuḥ. Gadgada-girā. Kadā tava-nāma-grahaṇe bhaviṣyati (Śikṣāṣṭaka 6). There is dissatisfaction, that 'When My heart will be throbbing? When torrents of rain will come out from My eyes? When My speech will be faltering? When that day will come?' That means this ordinary way He's not satisfied. That is the ecstatic summit: one becomes like a madman, chanting Hare Kṛṣṇa. So He is expecting, 'When that stage will come?' This stage comes when one is in the summit of chanting, this stage, aṣṭa-śakti-vidhā, eight kinds of transformation. So Caitanya Mahāprabhu is putting forward that 'When that stage will come?' Dissatisfaction. This is dissatisfaction. He says, 'I have not a pinch of devotion to Kṛṣṇa.' Even after crying, even coming to that stage of crying, He says, 'No, it is not the stage. I am crying just to make a show that I am a great devotee. I do not love Kṛṣṇa. The evidence is that I am still living. Without Kṛṣṇa and still I'm living. That is My imperfection. If I would have been really lover of Kṛṣṇa, without Kṛṣṇa I would have long, long ago died. But that I have not done. I am still living.' So who can show dissatisfaction like this? He says that 'I am still living. This is the evidence that I do not love Kṛṣṇa.' Even coming to the crying stage, first of all He said, 'When I shall cry incessantly for want of Kṛṣṇa?' And again coming to that stage, He is still dissatisfied. He says, 'I am simply crying just to make a show. I do not love Kṛṣṇa. If there was pinch of love for Kṛṣṇa, then I would have died long, long ago without Kṛṣṇa.' This is dissatisfaction. Who can show such kind of dissatisfaction? And who can feel such dissatisfaction? So the best utility is this Kṛṣṇa consciousness, from any philosophical point of view."
(Srila Prabhupada Philosophy Discussion on John Stuart Mill)