Ramblings on Inference and Doubt

Note: This post was originally published on my old blog on Quora. Please forgive my teenage edginess.

I’ve been contemplating over the past few months over religion, God’s existence (or non-existence), and the philosophical implications and underpinnings of free will and such. One school of thought that caught my attention was the Lokayata school of Vedic philosophy. I was introduced to this line of thought in Amartya Sen’s The Argumentative Indian and found it compelling given its atheistic inclinations and grounding of all knowledge in empiricism, a feature rather uncommon in religious philosophies.

Central to Lokayata philosophy is the constant questioning of all propositions and inferences. “No inference can be made without doubt,” is the motto of Lokayata and arguably the basis for most of its philosophical advances that follow. However, there seems to be an unavoidable paradox within: the statement itself seems to be an inference made from experience and perception but expresses itself without doubt.

1. Suppose the statement “no inference can be made without doubt” is true.

2. Since (a) this statement is itself an inference and (b) implicit within any linguistic description of experience and/or perception is an inference that language can describe the world (i.e. when I say “the jacket is red” I am assuming implicitly that it is possible to convey the experience of the color “red” through English), there exists doubt over the original statement.

3. Thus, the statement should be amended to “it is possible that no inference can be made without doubt.”

4. This also implies the statement “it is possible that an inference can be made without doubt.”

5. Since possibility necessitates experience at some point in time*, this means that an inference must have been made without doubt at some point in time, thus contradicting (1).

*This step is sketchy. As the argument goes, since any perception of existence must be based in experience, if $X$ possibly exists, $X$ must have existed at some time. For example, if I say “UFOs possibly exist” this implies that UFOs must have existed at some point in time, as there would otherwise be no experience for us to base our perception off of. It is not necessary that the subject experienced UFOs or that humanity ever did; however, since the perception of UFOs didn’t appear out of nowhere, we must be able to trace back the history of this perception to some time or point where it existed. There is an inherent problem I see with this argument: (a) it is possible for a human to perceive something that never existed (say, 25th dimension). We may be able to imagine a world in which the perceived object exists (think abstract physics or mathematics!) without having any ground to base this perception. This is precisely the reason why our conceptions of God/higher dimensions are hazy.