Syntax - how to subtract 2 columns

I am trying to subtract 2 columns (control - congruent) in the data view to create a new column (priming effect).

What is the syntax for subtraction? I have tried several variations of the following without any luck:

compute PrimingEffect = subtract (Control - Congruent).



TS Contributor
Don't have SPSS installed but try using the menu option (Compute) to subtract the two cols (simply type in "Control - Congruent") and use the Paste button. Then you'll have the code in you syntax window