For example, two people who lean against one another in mutual support embody reciprocal causation.

While paying attention to their wider context, a person can appreciate that even more "linear," A to B types of causation also ultimately involve reciprocal attributes.

For example, a bird can eat a whole worm because the worm is the specific type of entity that it is. If the worm were a whole mountain instead, the bird would not be able to eat it. The worm's nature is relevant to causing the bird to embody the capacity to eat it. The bird and the worm causally effect one another and embody reciprocal causation.

Note

¹This definition, while strictly mine, in my opinion benefits from the reconstruction of Ayn Rand's ontological philosophy - and from his discussion of reciprocal causation - that Chris Matthew Sciabarra provided in his book, Ayn Rand: The Russian Radical.