Descartes (med. 1-2) vs. Spinoza (part 1-2)

Benedict Spinoza Part1-2 and Decartes meditation1-3

QUESTION 3 Who starts out their project by arguing that that we can be certain that we exist? On that account, why can we be certain of this? What issue does this solve? QUESTION 3 Who starts out their project by arguing that that we can be certain that we exist? On that account, why can we be certain of this? What issue does this solve