Leonardo, being human, was not exempt from making mistakes. Though it sounds trite, the old saying is true: even geniuses make mistakes. Einstein, one of history's greatest intellectuals, was eventually proven wrong on certain parts of his theories. Leonardo also made several known errors. But did he let his mistakes rule his life? Read on to see how they affected his reputation.

Everyone Makes Mistakes

Some of Leonardo's errors were due simply to lack of information. The precise nature of human anatomy, with all its functioning and interrelating systems, was only starting to be understood in the fifteenth century. Leonardo performed “autopsies” on cadavers and made careful studies, but he had no formal medical training and was likely missing the big picture. For example, Leonardo made several sketches of a woman's womb, complete with uterus, fetus, and umbilical cord. However, he misjudged the size and shape of the placenta, and actually drew it more like a cow's.

Theories in Name Only

Along those same lines, Leonardo occasionally championed popular but flawed theories. He was, for example, a fan of physiognomy, which held that it was possible to determine a person's personality and character by studying his facial features and head shape. This theory was first published by Barthelemy Cocles in 1533, though the ideas had already been floating around for some time. In the nineteenth century, some physiognomists used this theory to try to predict who would be a murderer or thief. Sounds dangerous, doesn't it?

This concept was, of course, fundamentally biased and had no basis in science. In this specific case, Leonardo committed an error in judgment by believing that there was actual science involved in physiognomy. He wasn't alone in his ignorance, though; physiognomy was held up as a valid analytical tool until the twentieth century.

Technical Errors

One of Leonardo's more technical mistakes concerns his design for a military armored tank. If you examine the details of his system of wheels underneath the carriage, it is clear that the wheels would have actually been turning in opposite directions. The wheels would have spun harder and faster until the entire tank collapsed in a heap of metal and smoke. There are twotheories about this peculiarity: some think that Leonardo genuinely made a mistake in the design, while others feel that he probably made this error deliberately, so as to ensure that his design could not be stolen and copied later. You have to wonder, though, why he would go to all the trouble of sketching and detailing something that he probably knew would never work.

One thing to remember about the errors in Leonardo's work is that, during the Renaissance, artwork was often done collaboratively. Works that are attributed to Leonardo may actually have been done by others in his workshop. He had a number of students throughout his lifetime, and their skills were less developed (and more prone to error).

Consider Leonardo's drawing of Isabella d'Este from 1500. The cartoon sketch showed some of the figure, notably the arm, out of proportion; the musculature was also incorrect, and the figure would not have seemed lifelike. Given Leonardo's careful attention to anatomical detail, it seems likely in this case that one of his students made these mistakes in the sketch.

The vast majority of Leonardo's work was of superb quality and highly accurate. The only reason we're able to find these few flaws is because they stand out—his mistakes were quite rare. Of course, in the case of a genius such as Leonardo, his work has been scrutinized to a very high degree, and thus every possible error has been found.