Scientists

Archimedes

• Archimedes of Syracuse (c.287 BC - c. 212 BC) was an ancient Greek mathematician, physicist and engineer. Although little is known about his life, he is regarded as one of the most important scientists in classical antiquity. In addition to making important discoveries in the field of mathematics and geometry, he is credited with producing machines that were well ahead of their time.

• The Ancient Roman historians showed a strong interest in Archimedes and wrote several biographies relating to his life and works, while the few copies of his treatises that survived through the Middle Ages were a major influence on scientists during the Renaissance.

• Archimedes produced the first known summation of an infinite series with a method that is still used in the area of calculus today.

• Archimedes was a famous mathematician whose theorems and philosophies became world known. He gained a reputation in his own time which few other mathematicians of this period achieved. He is considered by most historians of mathematics as one of the greatest mathematicians of all time.

• Aristotle (384 BC - March 7, 322 BC) was an ancient Greek philosopher, student of Plato and teacher of Alexander the Great. He wrote many books about physics, poetry, zoology, logic, rhetoric, government, and biology.

• Aristotle, along with Plato and Socrates, are generally considered the three most influential ancient Greek philosophers in Western thought. Among them they transformed Presocratic Greek philosophy into the foundations of Western philosophy as we know it. The writings of Plato and Aristotle form the core of Ancient philosophy.

• Aristotle placed much more value on knowledge gained from the senses and would correspondingly be better classed among modern empiricists (see materialism and empiricism). He also achieved a "grounding" of dialectic in the Topics by allowing interlocutors to begin from commonly held beliefs (Endoxa); his goal being non-contradiction rather than Truth. He set the stage for what would eventually develop into the scientific method centuries later. Although he wrote dialogues early in his career, no more than fragments of these have survived.

• The works of Aristotle that still exist today are in treatise form and were, for the most part, unpublished texts. These were probably lecture notes or texts used by his students, and were almost certainly revised repeatedly over the course of years. As a result, these works tend to be eclectic, dense and difficult to read.

Aristole

Diseases

Agnosia

• Agnosia is a rare disorder characterized by an inability to recognize and identify objects or persons. People with agnosia may have difficulty recognizing the geometric features of an object or face or may be able to perceive the geometric features but not know what the object is used for or whether a face is familiar or not. Agnosia can be limited to one sensory modality such as vision or hearing. For example, a person may have difficulty in recognizing an object as a cup or identifying a sound as a cough. Agnosia can result from strokes, dementia, developmental disorders, or other neurological conditions. It typically results from damage to specific brain areas in the occipital or parietal lobes of the brain. People with agnosia may retain their cognitive abilities in other areas.

Autism

• Autistic disorder (sometimes called autism or classical ASD) is the most common condition in a group of developmental disorders known as the autism spectrum disorders (ASDs).Autistic children have difficulties with social interaction, display problems with verbal and nonverbal communication, and exhibit repetitive behaviors or narrow, obsessive interests. These behaviors can range in impact from mild to disabling. Autism varies widely in its severity and symptoms and may go unrecognized, especially in mildly affected children or when more debilitating handicaps mask it. Scientists aren’t certain what causes autism, but it’s likely that both genetics and environment play a role.