(plural paradigm shifts) 1  A radical change in thinking from an accepted point of view to a new one, necessitated when new scientific discoveries produce anomalies in the current paradigm. ( US) A radical change in thinking from an accepted point of view to a new belief.
The use of IN GOD WE TRUST has not been uninterrupted. The motto disappeared from the five-cent coin in 1883, and did not reappear until production of the Jefferson nickel began in 1938. Since 1938, all United States coins bear the inscription.
1964 was the date on the last 90% silver coins. Silver coins were actually made up through the early part of 1966 but the 1964 date was used on all of those. 1965 was used on the clad coins that were made in that year. So any dime, half dollar or quarter with a date of 1964 is 90% silver. <br /> <br /> Kennedy Half Dollars produced from 1965 through 1969 were made with a 40% silver content.