Organicism is the idea that things in the natural world are all connected and like parts of one big organism. It's like if you think of your body as its own organism - all the different parts of your body, like your heart, skin, stomach, and bones, all work together to help make you healthy. Organicism is the idea that everything in nature is like this too - that every part of nature is connected, like a big organism, and all the parts work together to keep nature healthy.