Actualism is a way of thinking that suggests that only things that exist now (in the present moment) are real and can be known. If a thing doesn't exist right now, it isn't real. So, if you look out of your window and all you can see are houses, that's all that exists - nothing else matters. If something happened in the past, or if you believe something might happen in the future, that’s not real or important. All that matters is what’s happening right now.