Everyone in the material world is engaged in all kinds of political, philanthropic and humanitarian activities to make material life happy and prosperous, but this is not possible. One should understand that in the material world, however one may try to make adjustments, he cannot be happy.
To cite an example, if you take a fish out of water, you can give it a very comfortable velvet bedstead, but still the fish cannot be happy; it will die. Because the fish is an animal of the water, it cannot be happy without water. Similarly, we are all spirit soul; unless we are in spiritual life or in the spiritual world, we cannot be happy. That is our position.
Everyone is trying for that spiritual realization. But we do not know. Therefore, we are trying to be happy here, in material conditions. We are becoming frustrated and confused. Therefore, we have to withdraw this understanding that we shall be very happy by making adjustments to this material world. Unless you take to Krishna consciousness, you cannot be happy. That is a fact. Therefore, we invite everyone to study and understand this great movement.
Ref: Chapter 3, Topmost Yoga System authored by Srila Prabhupada (Founder – Acharya, ISKCON)