Final answer:
The tall tree in MacNeice's 'The Truisms' symbolizes a place of higher observation, and knowledge, and a landmark of personal growth and wisdom, akin to a pursuit of enlightenment.
Step-by-step explanation:
In MacNeice's 'The Truisms', the tall tree symbolizes a point of observation and knowledge, towering above the commonplace and offering a broader perspective.
It stands as a landmark, signifying the potential for growth, longevity, and wisdom. Similar to the biblical 'Tree of Knowledge', the tree in MacNeice's poem can represent the pursuit of enlightenment and the courage to reach beyond the familiar in the quest for understanding.
In the context of each vignette where a tree features prominently, the symbolism may include themes such as adventure, mystery, heritage, and the intricacies of human emotions in relation to nature.