When I first spotted this newly-emerged Marbled White, he was scurrying along the footpath that crosses the butterfly field, trailing his shrivelled wings, and fluttering them from time to time in a vain attempt to fly. If he'd carried on like that his chances of survival would have been small - this is a well-used path, especially by dog walkers, and he would most probably have been either stepped on or eaten. But then one of his instincts kicked in, and he began looking for a stem to climb; he made an utter hash of it on the first few attempts, and wound up back down on the ground, but eventually he found this tangle of reasonably robust grasses, and hauled himself up it.
Having got himself upright, gravity was on his side in the business of inflating his wings, which he would do by pumping fluid into them; but until the wings were fully inflated and hardened enough for him to fly, he would be very vulnerable to predation. I watched him for a while, but inflation of the wings can take several hours, and I didn't have the time to stay kneeling next to him for that length of time to see if he managed to straighten himself out properly; so I wished him well and went on my way.
I've put some more photos of his struggles here, if you're interested.