# Is it possible to define assumptions?

It would be useful to be able of provide extra properties to the expressions, that allow Cadabra, SymPy or Mathematica to improve their simplification algorithms.

An existing example is the property Integer. It could be useful to include others like Real, Positive, Negative, or even a sort of In([<list of values>])

### Question

Is any of these properties currently defined?

Hi @kasper. So far none in particular, but given the expressions returned by SymPy, I believe that the simplification problem lies in the lack of assumptions.