Is Computer Science really a science? Computer scientists don’t apply the scientific method. Testing is currently essential for implementing software correctly, but only because we’re either too lazy or incapable of verifying correctness beforehand due to the extreme complexity of the systems and tools we use. It all boils down to manipulating an abstract machine, in most cases a register machine, which is a mathematical construct. The colors that appear on your monitor and the data written to your hard drive are merely side effects of the mathematical operations we compute.