A transcendence basis is a maximal family satisfying no nonzero polynomial relation over the base field. The example is deliberately concrete; it is a test of the statement, not a substitute for it.
Statement
An extension \(L/K\) is a vector space together with compatible multiplication. The degree \([L:K]\) is its vector-space dimension, so bases and minimal polynomials control field size.
The first display fixes the mathematical data. I label it \(\mathsf{data}\) mentally, while the next is the \(\mathsf{claim}\); the bridge between them is the displayed \(\Longrightarrow\), not an automatic implication.
Worked algebra
The following line is the smallest calculation that still exercises the mechanism. It keeps nested delimiters and the order of operations explicit.
Conceptual compression
The two-row display is also a debugging tool: if the conclusion changes when only notation changes, some hidden choice has entered the argument.
Caveat
The tower formula requires finite degrees for ordinary integer multiplication. Infinite extensions need cardinal dimensions or separate algebraic arguments.
The final box is a summary, not a new assumption; the proof still lives in the definitions and the intervening calculation. The source keeps each scope delimiter visible for later inspection.