The article I am responding to: http://bharatkalyan97.blogspot.in/2012/04/rig-veda-and-hindu-polytheism-dr-vijaya.html
I was not very impressed with the article, partly because it did not address any of my concerns, being an atheist, and partly because it used some non-philosophical rhetoric. As an atheist, I do not have the one god prejudice any more than I have the prejudice for tooth fairies or transcendental sandwiches. As a philosopher, I kind of distrust any paper that uses common fallacies like appeal to tradition.
The first issue I had were the culture war sophistry for the superiority of the Hindu faith. There is significant number of examples of defining polytheism in opposition to monotheism, but these depend on appeals to common practice and other fallacies. The prejudice for many gods is just as bad as the prejudice for one god. The prejudice for the old is just as bad as the prejudice for the new. The prejudice for the wide-spread is just as bad for the prejudice for the parochial.
The other big fallacy in the first section is the reverse naturalistic fallacy. In short, this fallacy is the assumption that if there is something morally objectionable about a theory or a theory's practitioners, it is false. This is done mostly by correctly detailing an imperial expansion of the monotheistic meme around the world. The belief of your conquers is not made false just because they harm people in the name of it or change the worldwide belief economy. This is no better than those who rejected evolution by natural selection because they morally objected to survival of the fittest, which had some political edge to it because of the Social Darwinists.
The only reason why polytheism in general bothers me more than monotheism is because polytheism populates our ontology with way more entities than monotheism. I rather avoid the superstition of the demon-haunted world, not to say monotheists, especially Catholics, are any less demon-haunted by their ridiculous beliefs about saints and sin. Philosophical monotheism tends to separate the woo from the natural world and put it into some abstract eternal realm in which its causal functions are limited to causing universes. Superficially at least, I rather do science with someone who was talking about the same natural world as I was. In other words, I prefer the least spiritual outlook as opposed to Dr. Vijaya Rajiva commitment to a 'deep spirituality' because I prefer the most accurate worldview, which so happens to be a world without spirits, beyond number or otherwise.
As for the philosophical arguments, I know a few for both sides. One long lasting idea which is not directly addressed in this paper are the reasons that led to monotheism in philosophy separate from the ideas of the Abrahamic faiths. The idea of one god became popular by those who thought that perfection is complete wholeness, without limits. This wholism is the one in monotheism, and the without limits is the omnipotence, omniscience, etc. Some of the Ancient Greek thinkers thought that their polytheistic gods imperfections (being prone to fear, anger, fickleness) demonstrated that they were not really gods. Plato created developed this philosophy so that this perfection was immaterial, with the understanding that material things are imperfect because they deteriorate. Plato saw the goal of love as an aspiration for the perfect, which he called Logos, which in Christianity became the Word. (In the beginning there was the Word, and the Word was God.")
As for polytheistic arguments, the one I am most familiar with is David Hume's The Natural History of Religion (1755) and Dialogues (1776). David Hume's The Natural History of Religion has similar arguments about the tolerance and social wellness of Polytheism compared to Monotheism, so I do suggest you read it if you have not already. The Dialogues include an argument from design, if my memory serves me right, that the universe is contains a variety of design therefore there should be variety amongst the creators as well. I am not sure if this was intended as a reductio ad absurdum, but you get the point.
As for the philosophical arguments given in the essay, it is interesting to note that she admits that there is no valid evidence that monotheists have for their god. As my atheist colleagues might say, 'what can be asserted without evidence can be dismissed without evidence.' I would only wish that Dr. Vijaya Rajiva would apply the same skepticism to polytheistic spirits.
The cosmological argument is weird because it feeds off a locally believed notion of the supreme cause that is particular to ancient India. That is that the supreme cause is beyond number. The argument that is presented in the text uses a reductio ad absurdum in order to attempt to demonstrate that the supreme cause must be beyond number because then 'number would be the cause'. In a sense, this is a gross misinterpretation of the monotheistic position. If oneness is understood as an aspect of perfection, it is perfection that is the cause not number. Wholeness (or oneness) is seen as essential to perfection in the theological and philosophical development of monotheism, and this is a gross misunderstanding of the term.
Beyond the objection from the way abstract concepts play in these a priori arguments, I reject the idea that there is a supreme cause anyways because there is no evidence that there is one and no logical need for one either. Speculation about how many metaphysical sandwiches exist outside our universe is just as fruitless an exercise of reason as positing entities and properties of those entities outside our universe. Most of this is because we do not know if what kind of causes cause universes or if universes are caused at all, so it is all speculation. This does not mean we cannot believe in theoretical entities beyond our direct observation, but the process of getting to those entities according to the most widely accepted epistemologies in post-analytic philosophy is too deep to discuss in this paper.