 Beliefs generated by rational doxastic practices can, however, be defeated by “over-rider”-systems internal to the practices themselves. In the case of “mystical perception”, the overrider-system includes a religion’s doctrinal teaching, by which the veridicality of purported mystical perceptions is tested. Alston argues that the “Christian mystical practice”, which generates significant self-support by the way it can “predict” or guide spiritual development, can be rationally engaged in, and hence produce beliefs about God that are prima facie justified. While mystical perceptions of the kind Alston deals with are often regarded as rare, Michael Rea has argued that experiences of God’s presence and of communication from God might be “widely available” (Rea 2018: Ch. 6–7). He suggests that the ability to experience God can be improved through spiritual practices and disciplines—an idea that is common in mystical traditions (see also Wynn 2013: 73–74).