You seem to be mixing up theory and hypothesis.

What field of science?
You absolutely can derive hypotheses from observations, considering that's how the vast majority are formed.
Observation: "This mould doesn't have any bacterial cultures growing around it"
Hypothesis: "The mould is producing a bactericidal compound which inhibits bacteria from growing around it"
Ru…

Wrong. A hypothesis is usually actually derived from observations, proposing a mechanism explaining usually a particular set of observable phenomena. Most rigourous scientists would say that falsifiability is a key component of a theory. Do you even basic science, bro?

Except falsifiability is a key component of what a theory is. This is just a hypothesis.

Would just like to point out that the bicameral mind hypothesis (I'm not even sure it has the merit to be called a theory) isn't really debatable and is more something neuroscientists drag out now and then to laugh at.