anumaana pramaaNa

If one has to infer something, he should have some basis for inference or should have some valid data to make some conclusions. The data is gathered directly or indirectly using pratyaksham or direct perception. One can never make of an inference without collecting or relying on perceptual data. (One can use inductive reasoning but for that reasoning to be valid, it requires subsequent confirmation by perceptual data). If inference is made without collecting or without having supportive data, the inference can only be a speculation or imagination. Such a speculative inference cannot be valid. For example if one wants to infer the age of a moon, he cannot look at the moon and estimate the age of the moon. He can truly estimate the age only by anumaana or inference. For that he needs to collect the requisite data - such as rocks from the moon and study using carbon dating etc. Using such a valid data one can infer the age of the moon. However, without any data and by looking at the moon if one estimates the age of the moon, then it will only be called a speculation and not inference. Therefore for any anumaana or inference to be valid, perceptual data is essential.