We do not deny the subjectivity of bhakti.  O.B.L.  Kapoor, author of Experiences in Bhakti: The Science Celestial, explains that the truths of bhakti, whatever they may be, are restricted to the hearts of the devotees (bhaktas).  Devotees cannot open their hearts and show them to others.  By contrast, the truths of science are supposedly open to all.  Scientists can repeat their experiments, and verify the results before everyone.  A devotee cannot present his truths for all to see.  Nevertheless, it is the claim of bhakti, that its truths, can be achieved by experimentation.  Insofar as that is possible, bhakti lays a valid claim to be a science; anyone who performs the experiment precisely will get the same result. 

However, one may argue that science proceeds from self-evident, or proven principles, while bhakti proceeds from articles of faith.  Even the very idea of revelation, which forms the theoretical basis of bhakti, is a matter of faith, because the data of revelation are not self-evident, and are not accepted by all.  How, then, can bhakti be called a science?

We reply by pointing out that one of the many ways in which science proceeds, the one most familiar to us, is based on acceptance of self-evident principles, which are then verified by experience; for example, the rules of arithmetic and geometry.  Another way that science works, is by beginning with an inspired or theoretical idea, a “hunch”, and proceeding to prove or disprove it, by observation and experimentation.  No one has any problem with this approach.  “Hunches” are played out all the time.  Sometimes they prove valid, sometimes not. 

Similarly, the bhakti understanding comes initially through revelation and verified afterwards.  Admittedly, the source of revelation may be sacred or divine, but there is no reasonable basis to rule out this approach, any more than we would rule out an inspired idea, or a hunch, which is later proven by experience.  The crucial issue is whether it can be proven, even if the procedure takes a very long time, and even if the procedure, by its very nature, has elements of subjectivity to it because it calls for an experience within one’s own self. 

The way revelation works, is that one accepts it with an initial faith, having first examined it under the cold light of logic and reason, then one proceeds to apply the recommended procedures that lead to direct experience.  

Herein, the role of revelation is no different from the situation in which a student of physics, or chemistry, initially accepts with faith, those principles and facts, presented by the authorities in his chosen science, which he may later verify by the scientific method.  Such faith is not blind; it is reasonable.  Similarly, the faith we invest initially in bhakti need not be blind. 

Admittedly, some practitioners may be invested in bhakti on the basis of blind faith, but whoever cares to undergo the exercise, will find that under critical scrutiny, all the first principles of bhakti can be supported by logic and reason; provided, as with physics or chemistry, that one approaches a qualified teacher in this field to aid one’s reasoning prowess. 

Ideally, one who develops faith in this way, will be able to repulse, with consistent logic, even the most aggressive assault of reason.  Blind faith is incapable of any such defense of its position.   

Thomas Aquinas, speaking of a “sacred science”, compared the working of revelation to the relationship between music and mathematics.  A musician may not become a mathematician, but the musician faithfully accepts the principles of music, which in reality proceed from the principles, established through mathematics.  In a way he can become an accomplished musician, yet he begins by accepting the “revelation” of mathematics that is inherent in music.  Therefore, the mathematical principles from which music proceeds are like the revelation from which bhakti proceeds. 

Sacred science, bhakti, proceeds by faithfully accepting the principles revealed by God.  Then, by applying the recommendations or procedures, which are also given as part of the revelation. 

Gradually the practitioner or experimenter experiences by direct perception his or her own self-transformation; for the science of bhakti aims at the self, at the subjective consciousness, and not at objects out there in the physical world. 

In conclusion, it is not intrinsic to science that one begins with doubt or with faith, as long as the procedure and laws of a given science, are in fact provable by experimentation, and observation.  Moreover, bhakti can be proven in this way.