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v. Third-person singular simple present indicative form of interpolate.

"The philosopher here stands for the stage of thought that goes beyond the stage of common sense; and the difference is simply that he 'interpolates' and 'extrapolates,' where common sense does not."

extrapolate   

interpolated    interpolates    interpolating   

cypher    reckon    figure    calculate    cipher   

extrapolate    interpolation   

renew    falsify    adulterate    transclude