Circumspect is defined by <em>Merriam-Webster Dictionary</em><em> </em>"careful to consider all circumstances and possible consequences." Cautious or careful are synonyms.
Root (same source) is "the usually underground part of a seed plant body that originates usually from the hypocotyl, functions as an organ of absorption, aeration, and food storage or as a means of anchorage and support, and differs from a stem especially in lacking nodes, buds, and leaves." It is also "proximal end of a nerve" or "the cause of something." According to the context, tuber, source, or foundation can be synonyms.
It is a tragic tale of a man who decides to travel alone through the hostile environment of the Yukon in sub- freeing temperatures and falls victims to the unrelenting and unforgiving power of nature.
a dishonest or unprincipled man. or an elephant or other large wild animal driven away or living apart from the herd and having savage or destructive tendencies.