What is the meaning of our life? William James’s answer to this question was, at firstsight, simple one. A significant life is a “strenuous life”, that is, life with some risks andsufferings. According to him, we should confront bravely against these sufferings. An easyand secure life , though comfortable at the beginning, will become boring in the end.But James added some mysticism to this plain claim. He insisted we should believethat a wider “unseen world” or “supernatural world” exists under our “visible world”.According to him, such a spiritual or religious belief will make our life more meaningful.But why did James need such mysticism? Are there any theoretical relations betweenthe “strenuous life view” and the “supernatural world view”? I will discuss about the relationof these two views and conclude as follows: (1) By believing in a “supernatural world”, wewill be able to face our life more seriously. (2) But not only that, we will be able to havesome special (or spiritual) experiences. (3) Such experiences will expand our “visible” worldin reality and make our life more integrated. Thus our life will become more meaningful.