Guest (2): Is this material knowledge of any value?
Prabhupāda: No. Material is valuable so far your material existence is concerned. That is also not valuable. Because if you try to protect this body by all kinds of knowledge, but it will not stay. And after giving up your this body, you have to accept another body. Then what is the value of material knowledge? This time you may have this human form of body; next time you may not have. Then what is the value of material knowledge?
Because you cannot change the order of transmigration of the soul from one body to another. That you have to accept according to your karma. So therefore material knowledge will not help me. Therefore they struggle so. You are under the grip of natural laws, daivi hy eṣā guṇamayī (BG 7.14). Natural . . . nature's law are very stringent. You cannot interfere with the . . . Prakṛteḥ kriyamāṇāni guṇaiḥ karmāṇi sarvaśaḥ (BG 3.27). The prakṛti, the nature, material nature is so strong that you cannot interfere with her business. That is not possible.
So your material knowledge will not help you, unless you have got Kṛṣṇa consciousness knowledge. You can . . . anyone can understand. Suppose if I want to protect this body with all hygienic principles, soaps and pumice and injection and medicine and so many things, does it mean that you shall live? Can you overcome the laws of nature? No, that is not possible. Can you overcome the laws of nature that you will not fall sick? No, that you cannot. Can you make any material laws or scientific knowledge that you will not become old? No. You cannot stop death, you cannot stop birth, you cannot stop old age, you cannot stop disease. So what is the value of your material knowledge? And these are the troubles.
Janma-mṛtyu-jarā-vyādhi-duḥkha-doṣānudarśanam (BG 13.9). Any intelligent man will see that, "What is the value of my material knowledge? I have to die. I have to be victim of disease and old age. Then what is value?" The best thing is that so long this material body is there, you have got the opportunity to develop your Kṛṣṇa consciousness, do that. That will save you from all dangers. Otherwise, nothing will save you. Simply śrama eva hi kevalam (SB 1.2.8), simply waste of time.
Chant Hare Kṛṣṇa.