Math function called with PK column ignores WHERE clause

A WHERE condition that uses a scalar function such as EXP is ignored and all rows are returned.

create table test (id integer primary key) ;
upsert into test values (1) ;
upsert into test values (2) ;
upsert into test values (3) ;
upsert into test values (4) ;
upsert into test values (5) ;
select ID, exp(ID) from test where exp(ID) < 10 ;

Result is:
1 2.718281828459045
2 7.38905609893065
3 20.085536923187668
4 54.598150033144236
5 148.4131591025766