Thanks to all of you who support me on Patreon. You da real mvps! $1 per month helps!! 🙂 https://www.patreon.com/patrickjmt !! Basic Conditional Probability Example. Here I look at a basic conditional probability example. Conditional probability is simply calculating a probability on the ‘condition’ that something already happened. In this case, the condition we assume is that John already selected a science card when selecting the next card.