Sometimes these senses are described as kāla sarpa. Kāla sarpa means the black cobra. As soon as the cobra touches—immediately dead. Similarly, if we allow this kāla sarpa to act in their own way, that means we are inviting death at every moment. Therefore those who are too much bodily attached, for them this yoga system is controlling the senses, yoga indriya saṁyamaḥ. Yoga does not mean to increase the power of sense gratification. Yoga means controlling the senses.
So the Bhaktivinoda Ṭhākura says that this network of ignorance, where the senses are like black cobra, out of all those senses the tongue is the greatest black cobra. Tā'ra madhye jihvā ati, lobhamoy sudurmati. The tongue, if you practice . . . just, for example, nobody learns smoking from the birth, but when he's habituated, then they are as chain smoker, one cigarette after another, one cigarette after . . . you see. This is simply by bad association. Therefore Bhaktivinoda Ṭhākura said that tā'ra madhye jihvā ati lobhamoy sudurmati. Because we have indulged this tongue to increase his greediness, therefore we see so much advertisement of liquor and cigarettes and so many, teas and coffee. Simply it is practice.
So as you have practice, by practice you have increased so-called demands of your body, you can decrease it also. Just like these boys. They were practiced to all these things, but since they have taken to Kṛṣṇa consciousness, by practicing they have given up everything. So anything artificial we may be habituated, but you can give it up.
Therefore here it is said, kāmasya nendriya prītiḥ. You should not introduce sense gratification for maintaining your body. Your body can be maintained very nicely if you take simple food made of rice, wheat, vegetable, little ghee and little milk. That's all. And you can get all these things anywhere, any part of the world, and you can offer to Kṛṣṇa.
Kṛṣṇa also says, patraṁ puṣpaṁ phalaṁ toyaṁ yo me bhaktyā prayacchati (BG 9.26). Any part of the world, any condition of life, you can secure these things. In Africa we have been in the interior, African villages. They are supposed to be uncivilized, but I don't think. They have got enough of these things, patraṁ puṣpaṁ phalaṁ toyam, anywhere. And they are being taught by this Kṛṣṇa consciousness movement to offer to Kṛṣṇa and take.
Therefore, this artificial civilization for sense gratification is not very good. It is not good for us. We may gratify our senses while we are living, but when we quit this body, we are completely under the grip of material nature. Prakṛteḥ kriyamāṇāni guṇaiḥ karmāṇi sarvaśaḥ (BG 3.27). And when you are on the clutches of prakṛti, you cannot dictate that "Give me this kind of body." That will be decided by superior authority, daiva netreṇa, karmaṇā daiva ne.
These are the scientific knowledge. But unfortunately, there is no culture of this scientific knowledge. Superficially, simply for sense gratification, that is going on in the name of advancement of civilization. Actually it is very risky civilization. Suppose after this body, human form of body, if I get the body of an animal or a tree. There is every chance. Wherefrom the tree comes? Wherefrom the tiger comes, the cat comes, the dog comes? There are demigods also. So you can get any form of life. Dehāntaram. Kṛṣṇa says personally, tathā dehāntara. This is bogus theory that after death everything is finished. No.