Is Life Worth Living? asks William James
In Is Life Worth Living? by William James James says: “Pessimism is essentially a religious disease.”
He clarifies thusly: This “is why I call pessimism an essentially religious disease. The nightmare view of life [arises from] the contradiction between the phenomena of Nature and the craving of the heart to believe that behind Nature there is a spirit whose expression Nature is.”
The “disease” is the “craving of the heart to believe” that Nature is saying something; that it has a spirit; that there is a benevolent and caring God; that all is not pointless.
This thought can be compressed thusly:
Life is worth living if you are undisturbed by pointlessness.
James is right but it is not the root of the matter. Pessimism is a purely chemical phenomenon. Proof: Smoke a little marijuana and life becomes worth living. What happens is that the chemical produces a change in philosophical outlook! Important being ‘the thing worth undertaking’ one may say that the change is:
From depression, where nothing is important
to elation, where anything is important.
And sometimes to anxiety, where everything is important. Pressingly so.