Peirce's "A Neglected Argument for the Reality of God" (link) is one of the most eccentric pieces ever written in the philosophy of religion. The points it makes are unusual, and they might take many readers by surprise.
According to our usual expectations, an argument for the reality of God must formulate grounds sufficient to justify the conclusion that God exists. Carrying such expectations, we will likely decide that Peirce’s paper affords at most a description of the “God-hypothesis”, rather than a reason for believing that the hypothesis is true. Peirce describes the effects that the hypothesis exerts on reasoners, mixes these descriptive claims with cajoling remarks about the optimism we assume whenever we engage in inquiry, and presents this mix as his “argument for the reality of God”.
The key to his presentation is that there is no categorical difference between what we should believe, and what we do believe. Peirce identifies the conditions one should set up, and the steps one should take, if one seeks the kind of experiences that prompt conviction of God’s reality. Those experiences, he implies, are the only things that could effectively perform the work of justifying the conclusion.
What we normally call an "argument", Peirce considers mere "argumentation" - a course of thinking is what constitutes a real argument, not the verbally formulated steps. Has Peirce accurately described the course of thinking that actually leads people to believe in a supreme being? And if so, is this (as he appears to think) sufficient to count as an argument in favor of that belief?