Within the confines of theism, the need for a multitude of Gods in Hinduism is not very clear, if not confusing. This apparent redundancy can be reconciled on a scientific basis. Before that, it is worthwhile to consider the basic premise of science. By this, I intend to ask the following question: “What lends credibility to a scientific law?”
Consider the Boyle’s law, discovered as early as in the 17th century. Now, to a current student of chemistry, the assurance given is that, under iso-thermal conditions, the product of pressure and volume of a fixed amount of gas is constant; and more importantly, this is verifiable and repeatable. Any scientific discovery gains credibility from its nature to be infinitely verifiable and repeatable. No matter how many times one repeats the experiment under specified conditions, Boyle’s law stands verified. Thus, infinite repeatability is what lends credibility to a scientific fact. Also, this infinite repeatability should be both in space and as well as in time. Any and every law will be verified by the many generations to come. Also, it wouldn’t do if Boyle’s law was verifiable only in India and not elsewhere. (Repeatability in space should be included, lest the Bermuda Triangle should come under the class of scientific phenomena). Singular occurrences cannot and do not come under the umbrella of science.
The phenomenon of God incarnating as Man can be harmonized with science if and only if it can be verified an infinite number of times. Thus, we are forced to concede infinite incarnations - both in space (across continents) and time (through the ages). This does not mean that the essence of each manifestation is different. It is the same principle repeating itself. In summary, the many gods in Hinduism is but a logical necessity within the confines of theism. The correctness of theism is a different discussion altogether.