With all his might, Bill could only scratch him. "The creature be too strong, too strong..." He nods in affirmation, and chuckles in that grim way people do when something's not funny. "Even so, I set forth, for his life. But I learned, 'twould have been worse to slay him, than to spare him, in the grand scheme." It's not a lie, but rather a very complex truth. Galactus was apparently a fundamental aspect of the universe, like molecular cohesion. It was beyond him to understand it fully.