Aristotle (384-322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. (Wikipedia)

Aristotle (384-322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. (Wikipedia)

Arthur Schopenhauer (1788-1860) was a German philosopher. (Wikipedia)

Arthur Schopenhauer (1788-1860) was a German philosopher. (Wikipedia)

Baruch Spinoza (Benedito de Espinosa)(Benedict de Spinoza)(1632-1677) was a Dutch philosopher of Portuguese Sephardi origin. One of the early thinkers of the Enlightenment and modern biblical criticism, including modern conceptions of the self and the universe, he came to be considered one of the great rationalists of 17th-century philosophy. Inspired by the groundbreaking ideas of René Descartes, Spinoza became a leading philosophical figure of the Dutch Golden Age. (Wikipedia) 

Blaise Pascal (1623-1662) was a French mathematician, physicist, inventor, writer and Catholic theologian. He was a child prodigy who was educated by his father, a tax collector in Rouen. Pascal's earliest work was in the natural and applied sciences where he made important contributions to the study of fluids, and clarified the concepts of pressure and vacuum by generalising the work of Evangelista Torricelli. Pascal also wrote in defence of the scientific method.

In 1642, while still a teenager, he started some pioneering work on calculating machines. After three years of effort and 50 prototypes, he built 20 finished machines (called Pascal's calculators and later Pascalines) over the following 10 years, establishing him as one of the first two inventors of the mechanical calculator. (Wikipedia)

Confucius (551-479 BC) was a Chinese philosopher and politician of the Spring and Autumn period. (Wikipedia)

Diogenes (Diogenes the Cynic)(412-323 BC), was a Greek philosopher and one of the founders of Cynic philosophy. He was born in Sinope, an Ionian colony on the Black Sea. (Wikipedia)

François-Marie Arouet (1694-1778), known by his nom de plume Voltaire, was a French Enlightenment writer, historian, and philosopher famous for his wit, his criticism of Christianity, especially the Roman Catholic Church, as well as his advocacy of freedom of speech, freedom of religion, and separation of church and state. (Wikipedia)

François-Marie Arouet (1694-1778), known by his nom de plume Voltaire, was a French Enlightenment writer, historian, and philosopher famous for his wit, his criticism of Christianity, especially the Roman Catholic Church, as well as his advocacy of freedom of speech, freedom of religion, and separation of church and state. (Wikipedia)

Friedrich Wilhelm Nietzsche (1844–1900) was a German philosopher, cultural critic, composer, poet, philologist, and Latin and Greek scholar.(Wikipedia)

Georg Wilhelm Friedrich Hegel (1770-1831) was a German philosopher and an important figure of German idealism. He achieved wide recognition in his day and—while primarily influential within the continental tradition of philosophy—has become increasingly influential in the analytic tradition as well.  His canonical stature within Western philosophy is universally recognized. (Wikipedia)

Georg Wilhelm Friedrich Hegel (1770-1831) was a German philosopher and an important figure of German idealism. He achieved wide recognition in his day and—while primarily influential within the continental tradition of philosophy—has become increasingly influential in the analytic tradition as well.  His canonical stature within Western philosophy is universally recognized. (Wikipedia)

Gottfried Wilhelm (von) Leibniz (Leibnitz) (1646-1716) was a prominent German polymath and one of the most important logicians, mathematicians and natural philosophers of the Enlightenment. As a representative of the seventeenth-century tradition of rationalism, Leibniz's most prominent accomplishment was conceiving the ideas of differential and integral calculus, independently of Isaac Newton's contemporaneous developments. Mathematical works have consistently favored Leibniz's notation as the conventional expression of calculus. It was only in the 20th century that Leibniz's law of continuity and transcendental law of homogeneity found mathematical implementation (by means of non-standard analysis). He became one of the most prolific inventors in the field of mechanical calculators. While working on adding automatic multiplication and division to Pascal's calculator, he was the first to describe a pinwheel calculator in 1685 and invented the Leibniz wheel, used in the arithmometer, the first mass-produced mechanical calculator. He also refined the binary number system, which is the foundation of all digital computers. (Wikipedia)

Henri-Louis Bergson (1859-1941) was a French philosopher who was influential in the tradition of continental philosophy. Bergson is known for his arguments that processes of immediate experience and intuition are more significant than abstract rationalism and science for understanding reality. (Wikipedia)

Heraclitus of Ephesus (c.535-c.475 BC) was a pre-Socratic Ionian Greek philosopher, and a native of the city of Ephesus, in modern day Turkey and then part of the Persian Empire. (Wikipedia)

I. K. Taimni (Iqbal Kishen Taimni, 1898–1978) was a professor of chemistry at the Allahabad University in India, and an influential scholar in the fields of Yoga and Indian philosophy. He was a leader of the Theosophical Society (Adyar).

Immanuel Kant (1724-1804) was an influential Prussian German philosopher in the Age of Enlightenment. (Wikipedia)

Johann Gottlieb Fichte (1762-1814) was a German philosopher who became a founding figure of the philosophical movement known as German idealism, which developed from the theoretical and ethical writings of Immanuel Kant. Recently, philosophers and scholars have begun to appreciate Fichte as an important philosopher in his own right due to his original insights into the nature of self-consciousness or self-awareness. Fichte was also the originator of thesis–antithesis–synthesis, an idea that is often erroneously attributed to Hegel. Like Descartes and Kant before him, Fichte was motivated by the problem of subjectivity and consciousness. Fichte also wrote works of political philosophy; he has a reputation as one of the fathers of German nationalism. (Wikipedia)

Laozi, also rendered as Lao Tzu and Lao-Tze, was an ancient Chinese philosopher and writer. He is the reputed author of the Tao Te Ching, the founder of philosophical Taoism.  (Wikipedia)