[Fai Mao]

I have had this type of discussion with science guys that fail to realize that science is based upon philosophy

[Pelham]

The philosophical field of Epistemology. The study of how we know what we know.

The scientific method is basically about measurement. But science is built upon assumptions that themselves can’t be measured.

[BroJoeK]

Fai Mao: "I have had this type of discussion with science guys that fail to realize that science is based upon philosophy."

Modern science -- natural science -- is based on at least two great assumptions:

1. Only natural explanations for natural processes, and
2. Natural processes operated the same in the distant past as they do today.

This article addresses the question: can an untestable hypothesis be classified as "scientific".
The answer is "no", but scientists can find some wiggle-room in definitions of "test" and "confirmation".

The correct term for untestable hypotheses is "speculation", regardless of how "scientific" it's thinkers may consider themselves.