Even if a materialist wants to enjoy developed material facilities, he can transfer himself to planets where he can experience material pleasures much more advanced than those available on earth. The best plan is to prepare oneself to return to the spiritual sky after leaving the body. However, if one is intent on enjoying material facilities, one can transfer himself to other planets in the material sky by utilizing yogic powers. The playful spaceships of the astronauts are but childish entertainments and are of no use for this purpose. The aṣṭāṅga-yoga system is a materialistic art of controlling air by transferring it from the stomach to the navel, from the navel to the heart, from the heart to the collarbone, from there to the eyeballs, from there to the cerebellum and from there to any desired planet. The velocities of air and light are taken into consideration by the material scientist, but he has no information of the velocity of the mind and intelligence. We have some limited experience of the velocity of the mind because in a moment we can transfer our minds to places hundreds of thousands of miles away. Intelligence is even finer. Finer than intelligence is the soul, which is not matter like mind and intelligence but is spirit, or antimatter. The soul is hundreds of thousands of times finer and more powerful than intelligence. We can thus only imagine the velocity of the soul in its traveling from one planet to another. Needless to say, the soul travels by its own strength and not with the help of any kind of material vehicle.
(Sri Caitanya Caritamrta----1:5:22----purport).

For the perfect yogī who has attained success in the method of leaving his body in perfect consciousness, transferring from one planet to another is as easy as an ordinary man's walking to the grocery store. As already discussed, the material body is just a covering of the spiritual soul. Mind and intelligence are the undercoverings, and the gross body of earth, water, air and so on is the overcoating of the soul. As such, any advanced soul who has realized himself by the yogic process, who knows the relationship between matter and spirit, can leave the gross dress of the soul in perfect order and as he desires. By the grace of God, we have complete freedom. Because the Lord is kind to us, we can live anywhere—either in the spiritual sky or in the material sky, upon whichever planet we desire. However, misuse of this freedom causes one to fall down into the material world and suffer the threefold miseries of conditioned life. The living of a miserable life in the material world by dint of the soul's choice is nicely illustrated by Milton in Paradise Lost. Similarly, by choice the soul can regain paradise and return home, back to Godhead.
(Sri Caitanya Caritamrta----1:5:22----purport).

At the critical time of death, one can place the vital force between the two eyebrows and decide where he wants to go. If he is reluctant to maintain any connection with the material world, he can, in less than a second, reach the transcendental abode of Vaikuṇṭha and appear there completely in his spiritual body, which will be suitable for him in the spiritual atmosphere. He has simply to desire to leave the material world both in finer and in grosser forms and then move the vital force to the topmost part of the skull and leave the body from the hole in the skull called the brahma-randhra. This is easy for one perfect in the practice of yoga.
Of course, man is endowed with free will, and as such if he does not want to free himself from the material world he may enjoy the life of brahma-pada (occupation of the post of Brahmā) and visit Siddhaloka, the planets of materially perfect beings, who have full capacities to control gravity, space and time. To visit these higher planets in the material universe, one need not give up his mind and intelligence (finer matter), but need only give up grosser matter (the material body).
(Sri Caitanya Caritamrta----1:5:22----purport).

The Bhagavad-gītā confirms that one will attain his next material body according to his desires at the time he leaves his body. The desire of the mind carries the soul to a suitable atmosphere as the wind carries aromas from one place to another. Unfortunately, those who are not yogīs but gross materialists, who throughout their lives indulge in sense gratification, are puzzled by the disarrangement of the bodily and mental condition at the time of death. Such gross sensualists, encumbered by the main ideas, desires and associations of the lives they have led, desire something against their interest and thus foolishly take on new bodies that perpetuate their material miseries.
Systematic training of the mind and intelligence is therefore needed so that at the time of death one may consciously desire a suitable body, either on this planet or another material planet or even a transcendental planet. A civilization that does not consider the progressive advancement of the immortal soul merely fosters a bestial life of ignorance.
(Sri Caitanya Caritamrta----1:5:22----purport).

Yogīs, however, try to perfect their lives, and therefore the Bhagavad-gītā enjoins that everyone should become a yogī. Yoga is the system for linking the soul in the service of the Lord. Only under superior guidance can one practice such yoga in his life without changing his social position. As already described, a yogī can go anywhere he desires without mechanical help, for a yogī can place his mind and intelligence within the air circulating inside his body, and by practicing the art of breath control he can mix that air with the air that blows all over the universe outside his body. With the help of this universal air, a yogī can travel to any planet and get a body suitable for its atmosphere. We can understand this process by comparing it to the electronic transmission of radio messages. With radio transmitters, sound waves produced at a certain station can travel all over the earth in seconds. But sound is produced from the ethereal sky, and as already explained, subtler than the ethereal sky is the mind, and finer than the mind is the intelligence. Spirit is still finer than the intelligence, and by nature it is completely different from matter. Thus we can just imagine how quickly the spirit soul can travel through the universal atmosphere.
(Sri Caitanya Caritamrta----1:5:22----purport).

In Brahmaloka there is an unlimited number of airplanes that are controlled not by yantra (machine) but by mantra (psychic action). Because of the existence of themind and intelligence on Brahmaloka, its residents have feelings of happiness and distress, but there is no cause of lamentation from old age, death, fear or distress. They feel sympathy, however, for the suffering living beings who are consumed in the fire of annihilation. The residents of Brahmaloka do not have gross material bodies to change at death, but they transform their subtle bodies into spiritual bodies and thus enter the spiritual sky. The residents of Brahmaloka can attain perfection in three different ways. Virtuous persons who reach Brahmaloka by dint of their pious work become masters of various planets after the resurrection of Brahmā, those who have worshiped Garbhodakaśāyī Viṣṇu are liberated with Brahmā, and those who are pure devotees of the Personality of Godhead at once push through the covering of the universe and enter the spiritual sky.
(Sri Caitanya Caritamrta----1:5:22----purport).

The topics that are about to be discussed between Lord Śrī Caitanya Mahāprabhu and Rāmānanda Rāya cannot be understood by a materialistic poet, nor by intelligence or material perception. Śrīla Bhaktisiddhānta Sarasvatī Ṭhākura states that the spiritual mellow can be realized only when one is situated on the transcendental platform beyond the material stage of goodness. That platform is called viśuddha-sattva (sattvaṁ viśuddhaṁ vasudeva-śabditam). Realization of the viśuddha-sattva platform is beyond the pale of the material world and is not perceived by bodily senses or mental speculation. Our identification with the gross body and subtle mind is different from spiritual understanding. Since theintelligence and mind are material, the loving affairs of Śrī Rādhā and Kṛṣṇa are beyond their perception. Sarvopādhi-vinirmuktaṁ tat-paratvena nirmalam: (CC.2:19:170) when we are free from all material designations and our senses are completely purified by the bhakti process, we can understand the sense activities of the Absolute Truth (hṛṣīkeṇa hṛṣīkeśa-sevanaṁ bhaktir ucyate.
(Sri Caitanya Caritamrta----2:8:193----purport).

One who is advanced in Kṛṣṇa consciousness can control the mind and intelligence and in this way rein in the horses, the senses, even though they are very powerful. One who can control the senses by his mind and intelligence can very easily approach the Supreme Personality of Godhead, or Viṣṇu, who is the ultimate goal of life. Tad viṣṇoḥ paramaṁ padaṁ sadā paśyanti sūrayaḥ. Those who are actually advanced approach Lord Viṣṇu, their ultimate goal. Such people are never captivated by Lord Viṣṇu's external energy, the material world.
(Sri Caitanya Caritamrta----2:11:37----purport).

Whatever state of being one remembers when he quits his body, O son of Kuntī, that state he will attain without fail. Therefore, Arjuna, you should always think of Me in the form of Kṛṣṇa and at the same time carry out your prescribed duty of fighting. With your activities dedicated to Me and your mind and intelligence fixed on Me, you will attain Me without doubt.
(Renunciation Through Wisdom).

The velocities of air and light are taken into consideration by the material scientist, but he has no information of the velocity of the mind and intelligence. We have some limited experience of the velocity of the mind, because in a moment we can transfer our minds to places hundreds of thousands of miles away. Intelligence is even finer. Finer than intelligence is the soul, which is not matter like mind and intelligence but is spirit, or antimatter. The soul is hundreds of thousands of times finer and more powerful than intelligence. We can thus only imagine the velocity of the soul in its traveling from one planet to another. Needless to say, the soul travels by its own strength and not with the help of any kind of material vehicle.
(Easy Journey to other Planets).

For the perfect yogī who has attained success in the method of leaving his body in perfect consciousness, transferring from one planet to another is as easy as an ordinary man's walking to the grocery store. As already discussed, the material body is just a covering of the spiritual soul. Mind and intelligence are the undercoverings, and the gross body of earth, water, air, etc., is the overcoating of the soul. As such, any advanced soul who has realized himself by the yogic process, who knows the relationship between matter and spirit, can leave the gross dress of the soul in perfect order and as he desires.
(Easy Journey to other Planets).

Of course man is endowed with free will, and as such if he does not want to free himself of the material world he may enjoy the life of brahma-pāda (occupation of the post of Brahmā) and visit Siddhaloka, the planets of materially perfect beings who have full abilities to control gravity, space, time, etc. To visit these higher planets in the material universe, one need not give up his mind and intelligence (finer matter), but need only give up grosser matter (the material body).
(Easy Journey to other Planets).

Our dear Lord, You are the Supreme Personality of Godhead, Kṛṣṇa, and You are also the supreme enjoyer. You have now appeared as the son of Vasudeva, a manifestation of the state of pure goodness. You are the predominating Deities of mind and intelligence, Aniruddha and Pradyumna, and You are the Lord of all Vaiṣṇavas. By Your expansion as the catur-vyūha—namely Vāsudeva, Saṅkarṣaṇa, Aniruddha and Pradyumna—You are the cause of the development of mind and intelligence. By Your activities only, the living entities become covered by forgetfulness or discover their real identity.
(Krsna Book).

When they saw that it was getting gradually darker, they stopped. Their mind and intelligence became absorbed in thoughts of Kṛṣṇa; they all imitated the activities of Kṛṣṇa and His speeches. Due to their heart and soul being completely given to Kṛṣṇa, they began to chant His glories, completely forgetting their family interests. In this way, all the gopīs returned to the bank of the Yamunā and assembled there, and expecting that Kṛṣṇa must return to them, they simply engaged in chanting the glories of Śrī Kṛṣṇa—Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare / Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare.
(Krsna Book).

"The ordinary conditioned human being may think that the conditioned soul, who is covered by his materialistic senses, mind and intelligence, is equal to Kṛṣṇa, but Lord Kṛṣṇa is just like the sun, which, although it sometimes may appear to be so, is never covered by the cloud, snow or fog, or by other planets during an eclipse. When the eyes of less intelligent men are covered by such influences, they think the sun to be invisible. Similarly, persons who are influenced by senses addicted to material enjoyment cannot have a clear vision of the Supreme Personality of Godhead."
(Krsna Book).

In the barbarian stage, or in the mode of ignorance, the senses are gratified in a very crude way, whereas in the mode of passion, or in civilized life, the senses are gratified in a polished manner. But when one is promoted to the mode of goodness, one can understand that the senses and the mind are engaged in material activities only due to being covered by perverted consciousness. When this perverted consciousness is gradually transformed into Kṛṣṇa consciousness, then the path of liberation is opened. So it is not that one is unable to approach the Absolute Truth by the senses and the mind. The conclusion is, rather, that the senses, mind and intelligence in the gross stage of contamination cannot appreciate the nature of the Absolute Truth, but when purified, the senses, mind and intelligence can understand what the Absolute Truth is. The purifying process is called devotional service, or Kṛṣṇa consciousness.
(Krsna Book).

At the time of death, the mind and intelligence of a living entity create the subtle form of a certain type of body for the next life. If the mind suddenly thinks of something not very congenial, one has to take a corresponding birth in the next life. On the other hand, if one can think of Kṛṣṇa at the time of death, he can be transferred to the spiritual world, Goloka Vṛndāvana. This process of transmigration is very subtle; therefore Śrīla Rūpa Gosvāmī advises devotees to train their minds in order that they will be unable to remember anything other than Kṛṣṇa.
(Nectar of Instruction).

The perfectional stage of spiritual life which one can experience even while being in the material world is described in the Twelfth Chapter of Bhagavad-gītā as follows: "One who is not envious but who is a kind friend to all living entities, who does not think himself a proprietor, who is free from false ego and equal both in happiness and distress, who is always satisfied and engaged in devotional service with determination and whose mind and intelligence are in agreement with Me—he is very dear to Me. He for whom no one is put into difficulty and who is not disturbed by anxiety, who is steady in happiness and distress, is very dear to Me. A devotee who is not dependent on the ordinary course of activities, who is pure, expert, without cares, free from all pains, and who does not strive for some result, is very dear to Me. One who grasps neither pleasure or grief who neither laments nor desires, and who renounces both auspicious and inauspicious things, is very dear to Me. One who is equal to friends and enemies, who is equipoised in honor and dishonor, heat and cold, happiness and distress, fame and infamy, who is always free from contamination, always silent and satisfied with anything, who doesn't care for any residence, who is fixed in knowledge and engaged in devotional service, is very dear to Me. He who follows this imperishable path of devotional service and who completely engages himself with faith, making Me the supreme goal, is very, very dear to Me." (Bg. 12.13-20)
(Teachings of Lord Caitanya).

The mood of the gopīs' emotional pursuit is called siddha-deha. This word indicates the pure spiritual body which is beyond the senses, mind and intelligence. Siddha-deha is the purified soul who is just suitable to serve the Supreme Lord. No one can serve the Supreme Lord as His associate without being situated in his pure spiritual identity. That identity is completely free from all material contamination. As stated in Bhagavad-gītā, a materially contaminated person transmigrates to another material body by material consciousness. At the time of death he thinks materially and is therefore transferred into another material body. Similarly, when one is situated in his pure spiritual identity and thinks of the spiritual loving service rendered to the Supreme Lord, he is transferred to the spiritual kingdom to enter into the association of Kṛṣṇa.
(Teachings of Lord Caitanya).