The philosophical terms in the book possess prime effect to hold a reader on a reassuring edge. The proof may be of an external world but it is felt internally! The instinct is eternally carried to have a constant inclination on what the author expresses.
Any religion, caste, race and creed reiterates commonly on a point of certainty:The existence of a Super Power. Here, the external world though doesn't mean the spiritual part of such a power, it does mean to say that something beyond us is frequently felt by those who seek to feel and find.
The supreme command of five elements such as Sky, Air, Water, Earth and Fire rule the existence of all living things. The very existence is heavily sidelined by emotions, struggles, deeds, feelings and all such related consequel expressions. And so what is beyond all these? Is it just a 'come and go' roof? No... It is more and more than that.
The proof of such an external world can be felt like a process of journey from body to soul and back. The soul is 'within' but unfortunately it is not felt instinctively as the 'instinct' itself is constantly out of reach. One can positively try to get access to the soul through instinct or to the instinct through soul. Either way can lead to find a distinctive proof of an external world.
When you imagine that it is there, of course it is there but it is not! But when you feel it is there you are certain to find it! The philosophical calculation is eternally evident.
Author Moore G.E. is marvelously exploring the possibilities of finding 'you' in yourself and thus leading to greater thinking powers and mental stabilities. The ongoing effects after going through the book is rendering a satisfaction of triumph! The illustration is rather highly convincing.
It is like practically getting a good hold on a link that is connecting you to the 'external world'.