Though one could be infinitely happy by just enjoying the nature and family and all the human-made things, there are still millions of people who are unhappy. In the developed countries there is very fortunate circumstance of having both God-given and man-made things. Still majority of people there are unhappy. In the developing countries, where for millions there is a real scarcity of even basic needs, people seem to be happy. There are some people who are engaged in difficult tasks and in warfare, and even incarcerated in prisons, and are still happy! We have just discussed the factors of happiness. Millions of people have them, still they are unhappy. There are millions of others who don't have them, yet they are happy!
You would realize that the mere availability and abundance of God given and human-made things is not enough. There is something else which should be right to be happy. Of course, it is our mind that must have right attitude towards and capacity to be happy.
Milton in Paradise Lost says,
'The mind is its own place, and in itself
Can make a Heaven of Hell, a Hell of Heaven.'
One can give various examples of how mind can influence our body::