It can be a little of a subjective matter to judge how smart a person is. Since this list is going to comprise of people who were not measured for IQ, we will consider overall achievements. This list is in no particular order and includes the smartest people of all time.

Leonardo da Vinci Da Vinci might be most well known for his paintings of The Last Supper and Mona Lisa, however, he is also revered as a genius who blurred the lines between art and science. Indeed, Leonardo da Vinci studied and made in-depth drawings, writings and charts on topics ranging from engineering, paleontology, architecture, botany and anatomy to astronomy, geography, music, zoology and geology. His drawings and descriptions number at over 4,000 pages and include similar concepts to things such as helicopters, airplanes, calculators, a tank, solar power and bicycles. He also drew detailed images of anatomy as he was allowed to dissect human bodies at various hospitals due to his fame. Da Vinci even had writings about plate tectonics.

Galileo Galilei This Italian scholar and scientist is known world-wide for his studies and findings that are the basis for much of modern astronomy and physics. His ideas were so revolutionary that he was twice accused of heresy by the church and later put under house arrest. During his studies he came up with the universal law of acceleration. Galileo also used a telescope to look up into the night sky. In doing so he found that the moon was neither flat nor smooth, but rather spherical with craters and mountains. He also discovered that Venus orbited the sun and that Jupiter also had moons. Galileo’s publication of a Dialogue Concerning the Two Chief World Systems was the last straw with the church as it revealed Aristotelian beliefs to be simple and false in comparison to Copernicus’ heliocentric theory. Galileo is often referred to as “The Father of Modern Science.”

Nikola Tesla Perhaps best known for his creation and use of safe alternating electrical currents, Tesla is the man who founded the method that generates and distributes power to cities and homes around the globe. He also made significant steps in advancing light bulbs, X-rays, remote controls and the electric motor. It is also widely believed that he was the real inventor of the radio, even though Guglielmo Marconi is often given all of the credit. Tesla was fluent in eight languages, he memorized complete books and it is said that he had a photographic memory. It is likely that he suffered from obsessive-compulsive disorder as he was obsessed with the number three; often performing certain routine tasks three times. He disliked round objects, shaking hands, jewelry and touching hair. In total, Tesla held about 300 patents for his inventions before his death.

Charles Darwin Charles Darwin was the scientist who built the foundation for the theory of evolution and popularized the concept of natural selection. Natural selection explains the process of evolution and how and why plants and animals slowly gain and lose certain traits over long periods of time. His 5 year voyage on the HMS Beagle allowed Darwin to study fossils and various species of animals. All of this led him to write and publish his major work “On the Origin of Species.” His ideas were revolutionary and vehemently rejected by the Church, but today have become widely accepted by the great majority of the scientific community.

Benjamin Franklin Benjamin Franklin was an inventor, author, businessman, politician, printer, writer, diplomat, colonel, abolitionist, philosopher and pioneer of ideas in his day. During his time he organized the first fire and police departments, created a circulating library, started Pennsylvania’s very first university and helped to open the first public hospital. He invented many things, including: bifocal lenses for glasses, the lightning rod, a glass instrument called the armonica and an improved heating stove. He was the first postmaster of the United States and he also showed his cartography skills by mapping the Gulf Stream to improve postal routes. Benjamin Franklin was indeed a very bright and gifted man with vast skills and many successes in his life.

Aristotle Aristotle is known by many to be a key founder of western philosophy. He was taught by famous philosopher Plato and later went on to be a teacher himself. He even tutored Alexander the Great. Later in life, he founded his own school called the Lyceum in Athens, Greece. Aristotle also wrote over 200 works, 31 of which are in circulation to this day. He was one of the first known people to try to classify the different types of animals. Aristotle also experimented with earth sciences and made note of the water cycle. His key philosophical works laid out the groundwork for proper reasoning skills and the methods for creating sound arguments.

Sir Isaac Newton One of the most influential scientists and mathematicians of all time, Isaac Newton laid the groundwork for classical mechanics, made key advancements in optics and is considered to be the co-founder of infinitesimal calculus. His publication of Principia explained universal gravitation and the laws of motion accurately. Through his mathematical depiction of gravity, and in combination with Kepler’s laws of planetary motion, Newton solidified the heliocentric model as fact. Additionally, Newton created the first reflecting telescope, did studies on the speed of sound and devised the empirical law of cooling.

Albert Einstein Albert Einstein is best known for his theory of general relativity. As a theoretical physicist he devised the mass-energy equivalence equation of E = mc2 as well as discovering the law of the photoelectric effect which he won the Nobel Prize in Physics for in 1921. This finding was monumental in creating quantum theory. He is also famous for warning President Franklin D. Roosevelt of the potential of the creation of the atomic bomb, which led to the U.S. starting up the Manhattan Project. He also worked to solve issues with quantum theory and statistical mechanics which resulted in his findings regarding the motion of molecules and particle theory.

Plato Plato is widely considered to be one of the greatest philosophers of all time. His publication the Republic combines political philosophy, epistemology, metaphysics, ethics and psychology into one system of thought. The topics of courage, justice, moderation, wisdom, love and art are common throughout his works. His writings are widely read to this day as his arguments and logic are still applicable and noteworthy. In academia today, Plato’s works are used to teach philosophy, ethics, logic, rhetoric, mathematics, and religion. Additionally, he founded the Academy in Athens, which was the first higher learning institution in the Western world.