The conditioned souls in the material world are all trying to satisfy their senses in various ways, but they have failed to do so because it is impossible to be satisfied by such efforts. The example of the fish on land is very appropriate. If one takes a fish from the water and puts in on the land, it cannot be made happy by any amount of offered pleasure. The spirit soul can be happy only in the association of the supreme living being, the Personality of Godhead, and nowhere else.
[Srila Prabhupada from Srimad Bhagavatam 3.2.11]