- complete luck; nothing but plain luck. I have no skill. I won by pure luck. (McGraw-Hill Dictionary) (Macmillandictionary.com)
- Curiously, as Ngram shows, the three expressions "pure luck, blind luck, dumb luck." have all been used from the same period, the middle of the 18th century.
1) The use of pure is quite intuitive and refers to something
- Complete; utter: pure folly. (AHD)
- Fortuna (Latin: Fortūna, equivalent to the Greek goddess Tyche) was the goddess of fortune and personification of luck in Roman religion. She might bring good luck or bad: she could be represented as veiled and blind, as in modern depictions of Justice, and came to represent life's capriciousness. (Wikipedia)
~ But what does 'dumb' refer to? How was it that this term came to be associated with luck?