His earliest work dealt mainly with mathematical subjects, and especially with quaternions (q.v.), of which he may be regarded as the leading exponent after their originator, Hamilton.
The prime exponent of the spurious religion is Simon Magus.
The new Hebrew Piyut found its first important exponent in Kalir, who was not a Spaniard.
As an exponent of universal evolution Haeckel is more consistent than Spencer.
Carlyle was the exponent of many of the deepest convictions of his time.
