[aortega]

>Theory: In science, a well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses.

...that can be wrong and often are replaced by better theories as more tests and better explanations came out.

Science is based in doubt. If you are too sure of a scientific theory, you are missing what science really is about and what you need is religion.

[jballanc]

Falsifiability is a feature of every element of science. Something that is not falsifiable isn't science. Period.

But a Theory is not a guess. It is a framework built from individual pieces, some of which may be hypotheses (effectively guesses) that have been tested and found to hold within the larger structure of that framework.

[aortega]

If you are based in individual pieces that may be effectively guesses, how you are not also a guess?

[jballanc]

Try formulating your question again, but this time don't leave out the part where I wrote "that have been tested and found to hold".

[chc]

Because you have been tested. The term "guess" implies lack of good grounding.

[BlackDeath3]

The reason that theories are not referred to as "guesses" is because there is, in theory (pun intended), an enormous chasm of evidence between a theory, and a guess/hypothesis.

Nothing is known with absolute certainty. What is the point is referring to everything as a "guess" simply because it isn't known for certain? Context is important here.

[saraid216]

Fallibility doesn't make it a "guess".