Why do humans believe that there is life after death? It is probably a myth that was carried over generations from our early ancestors who did not know much about the universe and the evolution or decent of humans.
Our ancestors only had past experiences and folk stories to go by to determine their existence and the meaning behind it. This is how the idea that there is a higher creator came about and persisted over many generations because it was so believable by the average person. It gave them hope that there could be more out there for them because life itself was a gift given to them or earned by them. However, such a belief is very powerful because it completely displaces the fact of death which is a biological phase in all life and this is the reason why the idea of life after death persists even today.
All living organisms undergoes the cycle of life and death. Lifespans vary but ultimately we all die and this organic matter is absorbed into the earth and atmosphere. If there was a creator and a so-called heaven there would be no reason to undergo the transition from life to death. As all of us know, when a loved one dies, including animals, we feel emotions of sadness, loneliness and anger which are negative emotions. Why would a creator put us through such prolonged misery if there already existed a means of living after death? It is a nonsensical and primitive thought.
It was quite normal for our early ancestors to believe that there was more to life because they lived in a less civilized society with very little knowledge of science and math-- fields of study that have given light to the order of the universe and the evolution of life. These fields are quite complex compared to the knowledge of our ancestors but nevertheless have paved the way for the advancement of society and intellect.
We have no need to rely on primitive knowledge such as the existence of a higher creator since we humans have made countless discoveries that negate the idea of god. We also do not need to incorporate such a falsity in our advanced knowledge of life and the universe because it is a contradictory idea and does not fit into the concepts of science and math. For if it did I for one would be a strong proponent for the existence of god. The evidence is just not there for the existence of god.
We all need to accept that there is no life after death or we will only continue to fool ourselves. People may argue that even if there is no god isn't it alright for people to feel hope and happiness that there could be light at the end of the tunnel simply for the sake of their feelings. However, this is an incomplete argument because this type of thought supports the possible existence of god-- an idea that many people fully incorporate into their every day lives. This is an idea that has promoted the killing of innocent people and the oppression of many more even today.
We cannot simply allow people to believe things that are not real for this only supports false ideas and creates new mythical ones further creating a chain of lies and a war against the truth. Moreover, it is not empathetic or respectful to accept that people have such false beliefs because it has a negative impact on what is true and real. We will only continue to live in a world of lies if we do not teach our children knowledge which is based on factual evidence.
There are other hopes and dreams which we can instill in our children and in ourselves such as the ability to be a knowledgeable citizen who can know what our limits and strengths are in life. The most wonderful thing in our existence today is the ability to freely learn about the nature of life and the universe and not about the hindering false claim that there is life after death.