Explain it until the borrowed language disappears

Technical language can conceal the exact point where understanding ends.

One of the best tests is to explain the idea in ordinary words, without leaning on the author’s vocabulary. If the explanation becomes vague, the problem is not simplicity. It is comprehension.

This is why teaching is such a useful form of learning. It exposes the gap between recognising an argument and being able to reconstruct it.

Clarity is not the removal of depth. It is evidence that the depth has been travelled.