user: Question: what is the total number of constancy where purity is falling
Columns: ['Acquisition', 'knowledge', 'penance', 'permanence of the body', 'constancy', 'purity']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Impurity', 'false conception', 'demerit', 'attachment', 'interestedness', 'falling']
SQL:

assistant: SELECT COUNT("constancy") FROM "Table" WHERE "purity" = 'falling';