Can you have 2 validation rules for one cell?

In my table i have a cell which has a drop down box with two choices - Yes, No. What i would like is one validation rule which would pop up if you click Yes and a different Validation rule if you click no.

If yes - Validation rule should say please move to line 20
If No - Validation rule should say please move to line 19

Is this at all possible or will i just have to have the one validation rule stating the two options?

Your help is much appreciated, thank you

To the explicit question, no, because that's not what validation is for.

But how about a cell next to the drop down box with something like:
=IF(<cell>="Yes","Please move to line 20",IF(<cell>="No","Please move to line 19",""))