According to materialists, the creation, development and destruction of the world are according to the rules of nature and not by the rules of God. They say that everybody wants happiness and by the fulfillment of every material desire, one can be happy. They believe that we are not eternal souls but mortal bodies, and by the fulfillment of the material senses one can be happy. The sense of seeing, hear, smell, touch, taste are five senses of our body. With the help of these senses we make use of this world. So, according to the materialists the means of happiness in this material world is this corporeal body.
On the other hand, according to spirituality, we are eternal souls and not this physical body. This body is destroyable and is made up of five structural elements (water, air, fire, ether and earth) whereas, the soul ('I') is spiritual, eternal, and is an eternal part of God. Bliss is the other name of God and being a part of "Him", we naturally desire for
raso vai saḥ
Now which way to choose?
This is a very difficult question for an individual to answer. Every religion claims to be perfect in its own ways. The answer to this can be explained in the following way:
We have two entities - the soul and the physical body. It is true that we will achieve our goal of attaining supreme bliss only by surrendering to God, and that the soul needs God. Similarly, we have to realize that this body requires the material world because this body is made up of five elements and this world is also comprised of these five elements.
No spiritualist can oppose a materialist, and no materialist can oppose a spiritualist. It is only with the help of this material body that devotional practice is made possible and without God-realization, mental afflictions, i.e. material desires, anger, jealousy, ego, etc. will never go away and we cannot have peace and happiness. Therefore, with the point of view of keeping our body healthy we have to do devotion. We have to keep our body healthy with the idea of serving and worshipping God. If we don't provide the necessary proteins, minerals, vitamins and all the required nutrients to our body, we will surely fall sick and instead of remembering God we will only remember pain and misery.
To summarize, we could say that we have to follow spirituality along with materialism. This can be explained with the help of example:
A nurse takes care of thousands of children in a hospital over her lifetime. She feeds and cleans them, gives them medicine, etc. She performs these tasks as part of her duty and not because she is attached to them. Her love and attachment are mostly for her children and family. She does not love the babies in the hospital as much as she does her own. The sickness of her own child brings her anxiety and pain. She will do everything possible to bring her own child back to normal health at the earliest.
But if a child falls sick in the hospital, the nurse will tend to it immediately and perform her duties well. Her reaction to the sickness will be quite normal and not emotional. She is not emotionally attached to the sick child. In the same way, we have to perform our material duties without any attachment for sake of duty and not being bothered of the loss or profit. This is called as Karm-yog.
tan hari meṅ man jagat meṅ, yah mahān ajñān ||
Attaching our mind to this material world and worshipping God with our body and material senses is a sign of great foolishness.
Hence, both materialism and spirituality are necessary for us because we are spiritual by nature — soul and we have this material body. We need this material world for existence.