The forming of conjectures.

In a conjectural manner.

Able to be conjectured upon.

In a conjecturable manner

plural of conjectural

plural of conjecturing

The quality of being conjecturable.

The property of being conjectural.

(philosophy) The belief that intentionally supposing that a proposition is true is a good reason to believe that proposition in the absence of evidence of its falsehood.

The theorem that the only simply connected, closed 3-dimensional manifold is a sphere.