Spurred on by a series of seminars in Poland in 1926 by Łukasiewicz that advocated a more natural treatment of logic , Jaśkowski made the earliest attempts at defining a more natural deduction , first in 1929 using a diagrammatic notation , and later updating his proposal in a sequence of papers in 1934 and 1935 .
Spurred on by a series of seminars in Poland in 1926 by Łukasiewicz that advocated a more natural treatment of logic , Jaśkowski made the earliest attempts at defining a more natural deduction .