But the Earth’s systems are highly complex, and complex systems do not respond to pressure in linear ways. When these systems interact (because the world’s atmosphere, oceans, land surface and lifeforms do not sit placidly within the boxes that make study more convenient), their reactions to change become highly unpredictable.

Small perturbations can ramify wildly. Tipping points are likely to remain invisible until we have passed them. We could see changes of state so abrupt and profound that no continuity can be safely assumed.
The non-linearity and highly unpredictable nature of natural systems should even be within the grasp of an arty farty literary type like you b.

My question to any climate change denialist is what do you actually think the net affect of a few millions extra tons of CO2 in an atmosphere will do - nothing?