Prabhupāda: The animals, for want of advanced consciousness, cannot follow any regulative principles. But by nature they have got some regulative principle. A human being, advanced consciousness, instead of using it for advance in spiritual life they use it for sense gratification and thus they become lower than the animals. So as soon as one becomes irregulated, without any sadācāra, then he doesn't care for any sinful activities for maintaining his body and soul together. He doesn't mind. Their philosophy is, what is called? "Existence is the first law of nature," or something like...
Guest (1): Self-preservation.
Prabhupāda: Self-preservation. So self-preservation... They do not know what is self-preservation. That is another ignorance. They consider this body as the self. Their self-preservation means to keep this body. And that is also not possible. If you do not follow regulative principles, it is not possible to keep your body in good condition. That is also not possible. Those who do not follow the regulative principles, mostly they are diseased, some kind. We find in the medical, modern medical shop the customers are educated people. Mass of people, they are not customers in the medical shop. You'll find it. They are not so much diseased. In every gentleman's house, modern, you'll find so many bottles of medicine. But you won't find such medical bottles in any house of less educated persons. They are not so diseased. So this is one of the items. If you want to advance in spiritual life you must follow the regulative principles to rectify your mistakes in the past life and this present life. Without being freed from all contamination nobody can understand God. That is not possible.