"forgot" to mention that $20 gift on your income tax forms?
Which isn't breaking the law in the US unless you've exceeded $13,000 annually to the donee, or $1M over their lifetime (3 states have state gift tax laws, but they all have exemptions for very low amounts that closely if not exactly mirror the federal laws).
"One of his disciples, the lesser-known Aristotle" means something wholly different than "one of his lesser-known disciples, Aristotle." As written, he's comparing the notoriety of the disciples. I think it's safe to say that, of Plato's disciples, Aristotle is the most well-known.
I'm not sure I'd characterize Aristotle as 'lesser known'.
Many people are unenthusiastic about their work.