Neville says the formula he teaches came out of years of his own searching and experimenting, that experience taught him

Date (happened)

before 1948 (possible)
qualifying source passages 527487; telling lecture nids 990
before 1 March 1948
telling lecture nid 990, certain delivery 1948-03-01

Told / reported

1 March 1948

Remain Faithful to Your Idea (nid 990), telling 990-4, told 1948-03-01

Persons

Neville says the formula he teaches came out of years of his own searching and experimenting, that experience taught him to condense the imaginary action into a single repeated act, and that his own many failures show he has not completely mastered the movements of his attention.