Cogito ergo sum. If you feel need to tag on a translation then don't let people learn themselves ...
Does not always work the other way round. Sum ergo cogito. Nah.
Maybe not but I don't think that thinking you are is as important as being who you are with the benefit of thinking first and more importantly thinking first and being who you are is is after all what all strive to be.
I think therefore I make an appointment to see the doctor.
Hope it's something serious otherwise you'll be wasting said do tors time and patience