Who was too lazy to calculate and invented a computer?

Answer 1

You are thinking of Charles Babbage, but no he was not lazy.

His primary concern was error in the calculations and in typesetting the final tables. It took enormous amounts of repetitive and largely redundant work by many human "computers" to calculate and cross check each other's results to find errors and when found to redo the calculation to try to get the right answers, then more work to verify the galley prints from the printshop had not changed the numbers and getting the printshop to retypeset the parts in error. Even after all this work errors remained in the printed tables.

These tables were used for everything at the time (e.g. ship navigation, insurance actuarial calculations, taxes, bank interest, mathematics) and in many of these fields a small error in just one entry of a table could result in significant financial losses!

Charles Babbage designed his Difference Engine (not really a computer) and his later Analytical Engine (a general purpose programmable digital computer) so that they could not make an error without instantly stopping, at which point the operator could either correct the error and restart or if necessary fix the machine's problem causing the error and restart the machine from the beginning. Both machines even typeset the printed tables automatically, so the printshop could not introduce errors after the calculation was done.

However he was never able to get funding to complete either machine.

It took another century and electronics instead of mechanics to give us computers.