The very nature of having faith in something implies an established uncertainty and a willingness to take the risk to believe in something specifically without proof. To prove God's existence would consequently eliminate the concept of faith altogether. Faith is an individualized human capability that is intimately related to the reaffirmation of God's existence as well as our own. Soren Kierkegaard, Danish philosopher and champion of the fideist argument, defines faith as a strictly subjective capacity, altogether separate from the objective function of the human psyche. The founder of the existentialist philosophical movement, Kierkegaard distinguishes the exclusivity of the relationship between science and religion to the point where there is no relationship at all.
Science is the embodiment of the objective and the impersonal.
Claiming that objective thought deserves no place in the question of faith, he furthermore explains that it is precisely objective thought that destroys the possibility of faith's fruition. Kierkegaard expounds upon the futility of even attempting to gather proof of God's existence in the first place. The very nature of a scientific inquiry is to begin with a hypothesis. Within that hypothesis, one must always reason from existence, not toward existence. Therefore the only way to prove God's existence is to take for granted that he already exists, to assume from the beginning that he exists.